Geometry Chapter 1 Resource Masters Consumable Workbooks Many of the worksheets contained in the Chapter Resource Masters booklets are available as consumable workbooks. Study Guide and Intervention Workbook Skills Practice Workbook Practice Workbook Reading to Learn Mathematics Workbook 0-07-860191-6 0-07-860192-4 0-07-860193-2 0-07-861061-3 ANSWERS FOR WORKBOOKS The answers for Chapter 1 of these workbooks can be found in the back of this Chapter Resource Masters booklet. Copyright © by The McGraw-Hill Companies, Inc. All rights reserved. Printed in the United States of America. Permission is granted to reproduce the material contained herein on the condition that such material be reproduced only for classroom use; be provided to students, teachers, and families without charge; and be used solely in conjunction with Glencoe’s Geometry. Any other reproduction, for use or sale, is prohibited without prior written permission of the publisher. Send all inquiries to: The McGraw-Hill Companies 8787 Orion Place Columbus, OH 43240-4027 ISBN: 0-07-846589-3 1 2 3 4 5 6 7 8 9 10 009 11 10 09 08 07 06 05 04 03 Geometry Chapter 1 Resource Masters Contents Vocabulary Builder . . . . . . . . . . . . . . . . vii Lesson 1-6 Study Guide and Intervention . . . . . . . . . 31–32 Skills Practice . . . . . . . . . . . . . . . . . . . . . . . . 33 Practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Reading to Learn Mathematics . . . . . . . . . . . 35 Enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Lesson 1-1 Study Guide and Intervention . . . . . . . . . . . 1–2 Skills Practice . . . . . . . . . . . . . . . . . . . . . . . . . 3 Practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Reading to Learn Mathematics . . . . . . . . . . . . 5 Enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Chapter 1 Assessment Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter Lesson 1-2 Study Guide and Intervention . . . . . . . . . . . 7–8 Skills Practice . . . . . . . . . . . . . . . . . . . . . . . . . 9 Practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Reading to Learn Mathematics . . . . . . . . . . . 11 Enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Lesson 1-3 Study Guide and Intervention . . . . . . . . . 13–14 Skills Practice . . . . . . . . . . . . . . . . . . . . . . . . 15 Practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Reading to Learn Mathematics . . . . . . . . . . . 17 Enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . 18 1 Test, Form 1 . . . . . . . . . . . . . . 37–38 1 Test, Form 2A . . . . . . . . . . . . . 39–40 1 Test, Form 2B . . . . . . . . . . . . . 41–42 1 Test, Form 2C . . . . . . . . . . . . . 43–44 1 Test, Form 2D . . . . . . . . . . . . . 45–46 1 Test, Form 3 . . . . . . . . . . . . . . 47–48 1 Open-Ended Assessment . . . . . . . 49 1 Vocabulary Test/Review . . . . . . . . 50 1 Quizzes 1 & 2 . . . . . . . . . . . . . . . . 51 1 Quizzes 3 & 4 . . . . . . . . . . . . . . . . 52 1 Mid-Chapter Test . . . . . . . . . . . . . 53 1 Cumulative Review . . . . . . . . . . . . 54 1 Standardized Test Practice . . . 55–56 Standardized Test Practice Student Recording Sheet . . . . . . . . . . . . . . A1 Lesson 1-4 Study Guide and Intervention . . . . . . . . . 19–20 Skills Practice . . . . . . . . . . . . . . . . . . . . . . . . 21 Practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Reading to Learn Mathematics . . . . . . . . . . . 23 Enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . 24 ANSWERS . . . . . . . . . . . . . . . . . . . . . . A2–A29 Lesson 1-5 Study Guide and Intervention . . . . . . . . . 25–26 Skills Practice . . . . . . . . . . . . . . . . . . . . . . . . 27 Practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Reading to Learn Mathematics . . . . . . . . . . . 29 Enrichment . . . . . . . . . . . . . . . . . . . . . . . . . . 30 © Glencoe/McGraw-Hill iii Glencoe Geometry Teacher’s Guide to Using the Chapter 1 Resource Masters The Fast File Chapter Resource system allows you to conveniently file the resources you use most often. The Chapter 1 Resource Masters includes the core materials needed for Chapter 1. These materials include worksheets, extensions, and assessment options. The answers for these pages appear at the back of this booklet. All of the materials found in this booklet are included for viewing and printing in the Geometry TeacherWorks CD-ROM. Vocabulary Builder Practice Pages vii–viii include a student study tool that presents up to twenty of the key vocabulary terms from the chapter. Students are to record definitions and/or examples for each term. You may suggest that students highlight or star the terms with which they are not familiar. There is one master for each lesson. These problems more closely follow the structure of the Practice and Apply section of the Student Edition exercises. These exercises are of average difficulty. WHEN TO USE These provide additional practice options or may be used as homework for second day teaching of the lesson. WHEN TO USE Give these pages to students before beginning Lesson 1-1. Encourage them to add these pages to their Geometry Study Notebook. Remind them to add definitions and examples as they complete each lesson. Reading to Learn Mathematics One master is included for each lesson. The first section of each master asks questions about the opening paragraph of the lesson in the Student Edition. Additional questions ask students to interpret the context of and relationships among terms in the lesson. Finally, students are asked to summarize what they have learned using various representation techniques. Study Guide and Intervention Each lesson in Geometry addresses two objectives. There is one Study Guide and Intervention master for each objective. WHEN TO USE Use these masters as WHEN TO USE This master can be used reteaching activities for students who need additional reinforcement. These pages can also be used in conjunction with the Student Edition as an instructional tool for students who have been absent. as a study tool when presenting the lesson or as an informal reading assessment after presenting the lesson. It is also a helpful tool for ELL (English Language Learner) students. Skills Practice There is one master for each lesson. These provide computational practice at a basic level. Enrichment There is one extension master for each lesson. These activities may extend the concepts in the lesson, offer an historical or multicultural look at the concepts, or widen students’ perspectives on the mathematics they are learning. These are not written exclusively for honors students, but are accessible for use with all levels of students. WHEN TO USE These masters can be used with students who have weaker mathematics backgrounds or need additional reinforcement. WHEN TO USE These may be used as extra credit, short-term projects, or as activities for days when class periods are shortened. © Glencoe/McGraw-Hill iv Glencoe Geometry Assessment Options Intermediate Assessment The assessment masters in the Chapter 1 Resources Masters offer a wide range of assessment tools for intermediate and final assessment. The following lists describe each assessment master and its intended use. • Four free-response quizzes are included to offer assessment at appropriate intervals in the chapter. • A Mid-Chapter Test provides an option to assess the first half of the chapter. It is composed of both multiple-choice and free-response questions. Chapter Assessment CHAPTER TESTS Continuing Assessment • Form 1 contains multiple-choice questions and is intended for use with basic level students. • The Cumulative Review provides students an opportunity to reinforce and retain skills as they proceed through their study of Geometry. It can also be used as a test. This master includes free-response questions. • Forms 2A and 2B contain multiple-choice questions aimed at the average level student. These tests are similar in format to offer comparable testing situations. • The Standardized Test Practice offers continuing review of geometry concepts in various formats, which may appear on the standardized tests that they may encounter. This practice includes multiplechoice, grid-in, and short-response questions. Bubble-in and grid-in answer sections are provided on the master. • Forms 2C and 2D are composed of freeresponse questions aimed at the average level student. These tests are similar in format to offer comparable testing situations. Grids with axes are provided for questions assessing graphing skills. • Form 3 is an advanced level test with free-response questions. Grids without axes are provided for questions assessing graphing skills. Answers • Page A1 is an answer sheet for the Standardized Test Practice questions that appear in the Student Edition on pages 58–59. This improves students’ familiarity with the answer formats they may encounter in test taking. All of the above tests include a freeresponse Bonus question. • The Open-Ended Assessment includes performance assessment tasks that are suitable for all students. A scoring rubric is included for evaluation guidelines. Sample answers are provided for assessment. • The answers for the lesson-by-lesson masters are provided as reduced pages with answers appearing in red. • A Vocabulary Test, suitable for all students, includes a list of the vocabulary words in the chapter and ten questions assessing students’ knowledge of those terms. This can also be used in conjunction with one of the chapter tests or as a review worksheet. © Glencoe/McGraw-Hill • Full-size answer keys are provided for the assessment masters in this booklet. v Glencoe Geometry NAME ______________________________________________ DATE 1 ____________ PERIOD _____ Reading to Learn Mathematics This is an alphabetical list of the key vocabulary terms you will learn in Chapter 1. As you study the chapter, complete each term’s definition or description. Remember to add the page number where you found the term. Add these pages to your Geometry Study Notebook to review vocabulary at the end of the chapter. Vocabulary Term Found on Page Definition/Description/Example acute angle adjacent angles uh·JAY·suhnt angle angle bisector collinear koh·LIN·ee·uhr complementary angles congruent kuhn·GROO·uhnt coplanar koh·PLAY·nuhr line segment linear pair (continued on the next page) © Glencoe/McGraw-Hill vii Glencoe Geometry Vocabulary Builder Vocabulary Builder NAME ______________________________________________ DATE 1 ____________ PERIOD _____ Reading to Learn Mathematics Vocabulary Builder Vocabulary Term (continued) Found on Page Definition/Description/Example midpoint obtuse angle perimeter perpendicular lines polygon PAHL·ee·gahn ray right angle segment bisector supplementary angles vertical angles © Glencoe/McGraw-Hill viii Glencoe Geometry NAME ______________________________________________ DATE 1-1 ____________ PERIOD _____ Study Guide and Intervention Points, Lines, and Planes Name Points, Lines, and Planes In geometry, a point is a location, a line contains points, and a plane is a flat surface that contains points and lines. If points are on the same line, they are collinear. If points on are the same plane, they are coplanar. Example Use the figure to name each of the following. A a. a line containing point A D B The line can be named as . Also, any two of the three points on the line can be used to name it. AB , AC , or BC C Lesson 1-1 N b. a plane containing point D The plane can be named as plane N or can be named using three noncollinear points in the plane, such as plane ABD, plane ACD, and so on. Exercises Refer to the figure. A 1. Name a line that contains point A. C m 2. What is another name for line D B E P m? 3. Name a point not on AC . 4. Name the intersection of AC and DB . 5. Name a point not on line or line Draw and label a plane is in plane 6. AB m. Q for each relationship. S Q. X A at P. 7. ST intersects AB P T Q B Y 8. Point X is collinear with points A and P. 9. Point Y is not collinear with points T and P. 10. Line contains points X and Y. © Glencoe/McGraw-Hill 1 Glencoe Geometry NAME ______________________________________________ DATE 1-1 ____________ PERIOD _____ Study Guide and Intervention (continued) Points, Lines, and Planes Points, Lines, and Planes in Space Space is a boundless, three-dimensional set of all points. It contains lines and planes. Example a. How many planes appear in the figure? There are three planes: plane O P N B N , plane O, and plane P. A b. Are points A, B, and D coplanar? Yes. They are contained in plane D O. C Exercises Refer to the figure. A 1. Name a line that is not contained in plane N. B C 2. Name a plane that contains point B. N D E 3. Name three collinear points. Refer to the figure. A B 4. How many planes are shown in the figure? D G C H I 5. Are points B, E, G, and H coplanar? Explain. F E J 6. Name a point coplanar with D, C, and E. Draw and label a figure for each relationship. 7. Planes 9. Line t contains point H and line plane N. Glencoe/McGraw-Hill M s 8. Line r is in plane N , line s is in plane intersect at point J. © t M andN intersect in HJ . M , and lines r and s N H J r t does not lie in plane M or 2 Glencoe Geometry NAME ______________________________________________ DATE 1-1 ____________ PERIOD _____ Skills Practice Points, Lines, and Planes Refer to the figure. A 1. Name a line that contains point D. B p D n C G 2. Name a point contained in line n. 4. Name the plane containing lines Lesson 1-1 3. What is another name for line p ? n and p. Draw and label a figure for each relationship. 5. Point K lies on RT . K 6. Plane J contains line s. T R s J lies in plane B and contains 7. YP point C, but does not contain point H. Y C 8. Lines q and in plane U. H f q P U B Refer to the figure. f intersect at point Z Z F 9. How many planes are shown in the figure? D E A 10. How many of the planes contain points F and E? C W B 11. Name four points that are coplanar. 12. Are points A, B, and C coplanar? Explain. © Glencoe/McGraw-Hill 3 Glencoe Geometry NAME ______________________________________________ DATE 1-1 ____________ PERIOD _____ Practice Points, Lines, and Planes Refer to the figure. j M 1. Name a line that contains points T and P. P S T R Q N h g 2. Name a line that intersects the plane containing points Q, N, and P. . 3. Name the plane that contains TN and QR Draw and label a figure for each relationship. and CG intersect at point M 4. AK in plane T. A T C M 5. A line contains L(4, 4) and M(2, 3). Line q is in the same coordinate plane but does . Line q contains point N. not intersect LM y G K M q x O N L Refer to the figure. T Q 6. How many planes are shown in the figure? W 7. Name three collinear points. A 8. Are points N, R, S, and W coplanar? Explain. S X M P R N VISUALIZATION Name the geometric term(s) modeled by each object. 9. 10. 11. tip of pin STOP 12. a car antenna © Glencoe/McGraw-Hill strings 13. a library card 4 Glencoe Geometry NAME ______________________________________________ DATE 1-1 ____________ PERIOD _____ Reading to Learn Mathematics Points, Lines, and Planes Pre-Activity Why do chairs sometimes wobble? Read the introduction to Lesson 1-1 at the top of page 6 in your textbook. • How many ways can you do this if you keep the pencil points in the same position? • How will your answer change if there are four pencil points? Reading the Lesson 1. Complete each sentence. a. Points that lie on the same lie are called points. b. Points that do not lie in the same plane are called points. c. There is exactly one through any two points. d. There is exactly one through any three noncollinear points. 2. Refer to the figure at the right. Indicate whether each statement is true or false. D U a. Points A, B, and C are collinear. C b. The intersection of plane ABC and line c. Line and line m is point P. B P A m do not intersect. m d. Points A, P,and B can be used to name plane U. e. Line lies in plane ACB. 3. Complete the figure at the right to show the following relationship: Lines , m, and n are coplanar and lie in plane Q. Lines and m intersect at point P. Line n intersects line m at R, but does not intersect line . Q n P R m Helping You Remember 4. Recall or look in a dictionary to find the meaning of the prefix co-. What does this prefix mean? How can it help you remember the meaning of collinear? © Glencoe/McGraw-Hill 5 Glencoe Geometry Lesson 1-1 • Find three pencils of different lengths and hold them upright on your desk so that the three pencil points do not lie along a single line. Can you place a flat sheet of paper or cardboard so that it touches all three pencil points? NAME ______________________________________________ DATE 1-1 ____________ PERIOD _____ Enrichment Points and Lines on a Matrix A matrix is a rectangular array of rows and columns. Points and lines on a matrix are not defined in the same way as in Euclidean geometry. A point on a matrix is a dot, which can be small or large. A line on a matrix is a path of dots that “line up.” Between two points on a line there may or may not be other points. Three examples of lines are shown at the upper right. The broad line can be thought of as a single line or as two narrow lines side by side. Dot-matrix printers for computers used dots to form characters. The dots are often called pixels. The matrix at the right shows how a dot-matrix printer might print the letter P. Draw points on each matrix to create the given figures. 1. Draw two intersecting lines that have four points in common. 2. Draw two lines that cross but have no common points. 3. Make the number 0 (zero) so that it extends to the top and bottom sides of the matrix. 4. Make the capital letter O so that it extends to each side of the matrix. 5. Using separate grid paper, make dot designs for several other letters. Which were the easiest and which were the most difficult? © Glencoe/McGraw-Hill 6 Glencoe Geometry NAME ______________________________________________ DATE 1-2 ____________ PERIOD _____ Study Guide and Intervention Linear Measure and Precision Measure Line Segments A part of a line between two endpoints is called a line segment. The lengths of M N and R S are written as MN and RS. When you measure a segment, the precision of the measurement is half of the smallest unit on the ruler. Example 2 Find the length of M N . M N cm 1 2 3 Find the length of R S . R 4 S in. The long marks are centimeters, and the shorter marks are millimeters. The length of N M is 3.4 centimeters. The measurement is accurate to within 0.5 millimeter, so M N is between 3.35 centimeters and 3.45 centimeters long. 1 2 The long marks are inches and the short marks are quarter inches. The length of R S 3 4 is about 1 inches. The measurement is accurate to within one half of a quarter inch, 1 8 5 8 S is between 1 inches and or inch, so R 7 8 Lesson 1-2 Example 1 1 inches long. Exercises Find the length of each line segment or object. 1. A cm 2. S B 1 2 3 T in. 3. 1 4. in. 1 2 cm 1 2 3 Find the precision for each measurement. © 5. 10 in. 6. 32 mm 7. 44 cm 8. 2 ft 9. 3.5 mm 10. 2 yd Glencoe/McGraw-Hill 1 2 7 Glencoe Geometry NAME ______________________________________________ DATE 1-2 ____________ PERIOD _____ Study Guide and Intervention (continued) Linear Measure and Precision On PQ, to say that point M is between points P and Q means P, Q, and M are collinear and PM MQ PQ. On AC, AB BC 3 cm. We can say that the segments are congruent, or A B B C . Slashes on the figure indicate which segments are congruent. Calculate Measures Example 1 1.2 cm D B A Example 2 Find EF. Q C Find x and AC. 2x 5 1.9 cm E M P F x A 2x B C Calculate EF by adding ED and DF. B is between A and C. ED DF EF 1.2 1.9 EF 3.1 EF AB BC AC x 2x 2x 5 3x 2x 5 x5 AC 2x 5 2(5) 5 15 Therefore, E F is 3.1 centimeters long. Exercises Find the measurement of each segment. Assume that the art is not drawn to scale. 1. R T 2.0 cm R 2. B C 2.5 cm S 3. X Z T 3 –21 in. 3 – 4 X Y in. 6 in. A 2 –43 in. B 4. W X 6 cm W Z C X Y Find x and RS if S is between R and T. 5. RS 5x, ST 3x, and RT 48. 6. RS 2x, ST 5x 4, and RT 32. 7. RS 6x, ST 12, and RT 72. 8. RS 4x, R S S T , and RT 24. Use the figures to determine whether each pair of segments is congruent. 9. A B and C D 10. X Y and Y Z 11 cm A 5 cm B X D 5 cm 11 cm 3x 5 C Y © Glencoe/McGraw-Hill 8 5x 1 9x 2 Z Glencoe Geometry NAME ______________________________________________ DATE 1-2 ____________ PERIOD _____ Skills Practice Linear Measure and Precision Find the length of each line segment or object. 1. 2. cm 1 2 3 4 5 in. 1 2 Find the precision for each measurement. 1 2 5. 9 inches 4. 12 centimeters Lesson 1-2 3. 40 feet Find the measurement of each segment. 6. N Q 7. A C 1–41 in. 1in. Q P 8. G H 4.9 cm A N 5.2 cm B F 9.7 mm C G H 15 mm Find the value of the variable and YZ if Y is between X and Z. 9. XY 5p, YZ p, and XY 25 10. XY 12, YZ 2g, and XZ 28 11. XY 4m, YZ 3m, and XZ 42 12. XY 2c 1, YZ 6c, and XZ 81 Use the figures to determine whether each pair of segments is congruent. 13. B E , C D 14. M P , N P B 2m C 3m E © 12 yd 3m 5m D Glencoe/McGraw-Hill M 12 yd 15. W X , W Z P Y 10 yd 5 ft N X 9 9 ft Z 5 ft W Glencoe Geometry NAME ______________________________________________ DATE 1-2 ____________ PERIOD _____ Practice Linear Measure and Precision Find the length of each line segment or object. 1. E 2. F in. 1 2 cm 1 2 3 4 5 Find the precision for each measurement. 1 4 4. 7 inches 3. 120 meters 5. 30.0 millimeters Find the measurement of each segment. 6. P S 7. A D 18.4 cm P 2–83 in. 4.7 cm Q 8. W X S A 1–41 in. C W X Y 89.6 cm 100 cm D Find the value of the variable and KL if K is between J and L. 9. JK 6r, KL 3r, and JL 27 10. JK 2s, KL s 2, and JL 5s 10 Use the figures to determine whether each pair of segments is congruent. 11. T U , S W 12. A D , B C T 2 ft S 2 ft A 13. G F , F E 12.7 in. B G 5x 3 ft U 3 ft W H 6x D 12.9 in. C 14. CARPENTRY Jorge used the figure at the right to make a pattern for a mosaic he plans to inlay on a tabletop. Name all of the congruent segments in the figure. F E A F B E C D © Glencoe/McGraw-Hill 10 Glencoe Geometry NAME ______________________________________________ DATE 1-2 ____________ PERIOD _____ Reading to Learn Mathematics Linear Measure and Precision Pre-Activity Why are units of measure important? Read the introduction to Lesson 1-2 at the top of page 13 in your textbook. • The basic unit of length in the metric system is the meter. How many meters are there in one kilometer? • Do you think it would be easier to learn the relationships between the different units of length in the customary system (used in the United States) or in the metric system? Explain your answer. Reading the Lesson Lesson 1-2 1. Explain the difference between a line and a line segment and why one of these can be measured, while the other cannot. 2. What is the smallest length marked on a 12-inch ruler? What is the smallest length marked on a centimeter ruler? 3. Find the precision of each measurement. a. 15 cm b. 15.0 cm 4. Refer to the figure at the right. Which one of the following statements is true? Explain your answer. B A C D B A C D A 4.5 cm D C 4.5 cm B 5. Suppose that S is a point on V W and S is not the same point as V or W. Tell whether each of the following statements is always, sometimes, or never true. a. VS SW b. S is between V and W. c. VS VW SW Helping You Remember 6. A good way to remember terms used in mathematics is to relate them to everyday words you know. Give three words that are used outside of mathematics that can help you remember that there are 100 centimeters in a meter. © Glencoe/McGraw-Hill 11 Glencoe Geometry NAME ______________________________________________ DATE 1-2 ____________ PERIOD _____ Enrichment Points Equidistant from Segments The distance from a point to a segment is zero if the point is on the segment. Otherwise, it is the length of the shortest segment from the point to the segment. A figure is a locus if it is the set of all points that satisfy 1 4 a set of conditions. The locus of all points that are inch A B from the segment AB is shown by two dashed segments with semicircles at both ends. 1. Suppose A, B, C, and D are four different points, and consider the locus of all points x units from A B and x units from C D . Use any unit you find convenient. The locus can take different forms. Sketch at least three possibilities. List some of the things that seem to affect the form of the locus. A C B X Y R B D A Y A X C P C S D B Q D 2. Conduct your own investigation of the locus of points equidistant from two segments. Describe your results on a separate sheet of paper. © Glencoe/McGraw-Hill 12 Glencoe Geometry NAME ______________________________________________ DATE 1-3 ____________ PERIOD _____ Study Guide and Intervention Distance and Midpoints Distance Between Two Points Distance on a Number Line A Pythagorean Theorem: B a Distance in the Coordinate Plane y a2 b2 c2 b B(1, 3) Distance Formula: AB | b a | or | a b | d (x2 x1)2 (y2 y1)2 A(–2, –1) x O C (1, –1) Find AB. A 5 4 3 2 1 B 0 1 2 AB | (4) 2 | | 6 | 6 3 Example 2 Find the distance between A(2, 1) and B(1, 3). Pythagorean Theorem (AB)2 (AC)2 (BC)2 (AB)2 (3)2 (4)2 (AB)2 25 AB 25 5 Distance Formula d (x2 x1)2 (y2 y1)2 AB (1 ( 2))2 (3 (1))2 AB (3)2 (4)2 25 5 Exercises Use the number line to find each measure. 1. BD 2. DG 3. AF 4. EF 5. BG 6. AG 7. BE 8. DE A B C –10 –8 –6 –4 –2 DE 0 F 2 G 4 6 8 Use the Pythagorean Theorem to find the distance between each pair of points. 9. A(0, 0), B(6, 8) 11. M(1, 2), N(9, 13) 10. R(2, 3), S(3, 15) 12. E(12, 2), F(9, 6) Use the Distance Formula to find the distance between each pair of points. 13. A(0, 0), B(15, 20) 14. O(12, 0), P(8, 3) 15. C(11, 12), D(6, 2) 16. E(2, 10), F(4, 3) © Glencoe/McGraw-Hill 13 Glencoe Geometry Lesson 1-3 Example 1 NAME ______________________________________________ DATE 1-3 ____________ PERIOD _____ Study Guide and Intervention (continued) Distance and Midpoints Midpoint of a Segment If the coordinates of the endpoints of a segment are a and b, Midpoint on a Number Line a b. then the coordinate of the midpoint of the segment is 2 If a segment has endpoints with coordinates (x1, y1) and (x2, y2), Midpoint on a Coordinate Plane Example 1 P x x 2 y y 2 1 2 1 2 then the coordinates of the midpoint of the segment are , . Find the coordinate of the midpoint of P Q . Q –3 –2 –1 0 1 2 The coordinates of P and Q are 3 and 1. 3 1 2 2 2 Q , then the coordinate of M is or 1. If M is the midpoint of P Example 2 M is the midpoint of P Q for P(2, 4) and Q(4, 1). Find the coordinates of M. x x 2 y y 2 22 4 41 2 1 2 1 2 M , , or (1, 2.5) Exercises Use the number line to find the coordinate of the midpoint of each segment. A B C –10 –8 –6 –4 –2 1. C E 2. D G 3. A F 4. E G 5. A B 6. B G 7. B D 8. D E D EF 0 2 G 4 6 8 Find the coordinates of the midpoint of a segment having the given endpoints. 9. A(0, 0), B(12, 8) 10. R(12, 8), S(6, 12) 11. M(11, 2), N(9, 13) 12. E(2, 6), F(9, 3) 13. S(10, 22), T(9, 10) 14. M(11, 2), N(19, 6) © Glencoe/McGraw-Hill 14 Glencoe Geometry NAME ______________________________________________ DATE 1-3 ____________ PERIOD _____ Skills Practice Distance and Midpoints Use the number line to find each measure. 1. LN 2. JL 3. KN 4. MN J –6 K –4 L –2 0 2 M 4 6 N 8 10 Use the Pythagorean Theorem to find the distance between each pair of points. 5. 6. y y S G O x O x F D 8. C(3, 1), Q(2, 3) 7. K(2, 3), F(4, 4) Use the Distance Formula to find the distance between each pair of points. 10. W(2, 2), R(5, 2) 11. A(7, 3), B(5, 2) Lesson 1-3 9. Y(2, 0), P(2, 6) 12. C(3, 1), Q(2, 6) Use the number line to find the coordinate of the midpoint of each segment. 13. D E 14. B C 15. B D 16. A D A –6 –4 B –2 C 0 2 D 4 6 E 8 10 12 Find the coordinates of the midpoint of a segment having the given endpoints. 17. T(3, 1), U(5, 3) 18. J(4, 2), F(5, 2) Find the coordinates of the missing endpoint given that P is the midpoint of N Q . 19. N(2, 0), P(5, 2) © Glencoe/McGraw-Hill 20. N(5, 4), P(6, 3) 15 21. Q(3, 9), P(1, 5) Glencoe Geometry NAME ______________________________________________ DATE 1-3 ____________ PERIOD _____ Practice Distance and Midpoints Use the number line to find each measure. 1. VW 2. TV 3. ST 4. SV S –10 –8 –6 T U –4 –2 V 0 W 2 4 6 8 Use the Pythagorean Theorem to find the distance between each pair of points. 5. 6. y y S Z O O x x M E Use the Distance Formula to find the distance between each pair of points. 7. L(7, 0), Y(5, 9) 8. U(1, 3), B(4, 6) Use the number line to find the coordinate of the midpoint of each segment. 9. R T 10. Q R 11. S T 12. P R P –10 Q –8 –6 R –4 –2 S 0 T 2 4 6 Find the coordinates of the midpoint of a segment having the given endpoints. 13. K(9, 3), H(5, 7) 14. W(12, 7), T(8, 4) Find the coordinates of the missing endpoint given that E is the midpoint of D F . 15. F(5, 8), E(4, 3) 16. F(2, 9), E(1, 6) 17. D(3, 8), E(1, 2) 18. PERIMETER The coordinates of the vertices of a quadrilateral are R(1, 3), S(3, 3), T(5, 1), and U(2, 1). Find the perimeter of the quadrilateral. Round to the nearest tenth. © Glencoe/McGraw-Hill 16 Glencoe Geometry NAME ______________________________________________ DATE 1-3 ____________ PERIOD _____ Reading to Learn Mathematics Distance and Midpoints Pre-Activity How can you find the distance between two points without a ruler? Read the introduction to Lesson 1-3 at the top of page 21 in your textbook. • Look at the triangle in the introduction to this lesson. What is the special B in this triangle? name for A • Find AB in this figure. Write your answer both as a radical and as a decimal number rounded to the nearest tenth. Reading the Lesson 1. Match each formula or expression in the first column with one of the names in the second column. a. d (x2 x1)2 ( y2 y1)2 i. Pythagorean Theorem ab 2 b. ii. Distance Formula in the Coordinate Plane c. XY | a b | iii. Midpoint of a Segment in the Coordinate Plane d. c2 a2 b2 iv. Distance Formula on a Number Line x x 2 y y 2 1 2 1 2 , e. v. Midpoint of a Segment on a Number Line 2. Fill in the steps to calculate the distance between the points M(4, 3) and N(2, 7). , d ( )2 ( )2 MN ( )2 ( )2 MN ( )2 ( )2 MN MN ). Lesson 1-3 Let (x1, y1) (4, 3). Then (x2, y2) ( Find a decimal approximation for MN to the nearest hundredth. Helping You Remember 3. A good way to remember a new formula in mathematics is to relate it to one you already know. If you forget the Distance Formula, how can you use the Pythagorean Theorem to find the distance d between two points on a coordinate plane? © Glencoe/McGraw-Hill 17 Glencoe Geometry NAME ______________________________________________ DATE 1-3 ____________ PERIOD _____ Enrichment Lengths on a Grid Evenly-spaced horizontal and vertical lines form a grid. You can easily find segment lengths on a grid if the endpoints are grid-line intersections. For horizontal or vertical segments, simply count squares. For diagonal segments, use the Pythagorean Theorem (proven in Chapter 7). This theorem states that in any right triangle, if the length of the longest side (the side opposite the right angle) is c and the two shorter sides have lengths a and b, then c2 a2 b2. R A C S D B I Q E Example L J Find the measure of EF on the grid at the right. Locate a right triangle with E F as its longest side. F K N M E 2 5 EF 22 52 F 29 5.4 units Find each measure to the nearest tenth of a unit. 1. IJ 2. M N 3. RS 4. Q S 5. I K 6. J K 7. L M 8. L N Use the grid above. Find the perimeter of each triangle to the nearest tenth of a unit. 9. ABC 10. QRS 11. DEF 12. LMN 13. Of all the segments shown on the grid, which is longest? What is its length? 14. On the grid, 1 unit 0.5 cm. How can the answers above be used to find the measures in centimeters? 15. Use your answer from exercise 8 to calculate the length of segment LN in centimeters. Check by measuring with a centimeter ruler. 16. Use a centimeter ruler to find the perimeter of triangle IJK to the nearest tenth of a centimeter. © Glencoe/McGraw-Hill 18 Glencoe Geometry NAME ______________________________________________ DATE 1-4 ____________ PERIOD _____ Study Guide and Intervention Angle Measure Measure Angles If two noncollinear rays have a common endpoint, they form an angle. The rays are the sides of the angle. The common endpoint is the vertex. The angle at the right can be named as A, BAC, CAB, or 1. B 1 A A right angle is an angle whose measure is 90. An acute angle has measure less than 90. An obtuse angle has measure greater than 90 but less than 180. Example 1 S R 1 2 C Example 2 Measure each angle and classify it as right, acute, or obtuse. T 3 Q P E D a. Name all angles that have R as a vertex. Three angles are 1, 2, and 3. For other angles, use three letters to name them: SRQ, PRT, and SRT. A B C a. ABD Using a protractor, mABD 50. 50 90, so ABD is an acute angle. b. Name the sides of 1. , RP RS b. DBC Using a protractor, mDBC 115. 180 115 90, so DBC is an obtuse angle. c. EBC Using a protractor, mEBC 90. EBC is a right angle. Exercises A B 4 1. Name the vertex of 4. 1 D 2. Name the sides of BDC. 3 2 C 3. Write another name for DBC. Measure each angle in the figure and classify it as right, acute, or obtuse. N M S 4. MPR P 5. RPN R 6. NPS © Glencoe/McGraw-Hill 19 Glencoe Geometry Lesson 1-4 Refer to the figure. NAME ______________________________________________ DATE 1-4 ____________ PERIOD _____ Study Guide and Intervention (continued) Angle Measure Congruent Angles Angles that have the same measure are congruent angles. A ray that divides an angle into two congruent angles is called an angle bisector. In the figure, PN is the angle bisector of MPR. Point N lies in the interior of MPR and MPN NPR. M N P R Q R Example Refer to the figure above. If mMPN 2x 14 and mNPR x 34, find x and find mMPR. Since PN bisects MPR, MPN NPR, or mMPN mNPR. 2x 14 x 34 2x 14 x x 34 x x 14 34 x 14 14 34 14 x 20 mNPR (2x 14) (x 34) 54 54 108 Exercises bisects PQT, and QP and QR are opposite rays. QS 1. If mPQT 60 and mPQS 4x 14, find the value of x. S T P 2. If mPQS 3x 13 and mSQT 6x 2, find mPQT. and BC are opposite rays, BF bisects CBE, and BA bisects ABE. BD E D 3. If mEBF 6x 4 and mCBF 7x 2, find mEBC. F 1 A 2 3 B 4 C 4. If m1 4x 10 and m2 5x, find m2. 5. If m2 6y 2 and m1 8y 14, find mABE. 6. Is DBF a right angle? Explain. © Glencoe/McGraw-Hill 20 Glencoe Geometry NAME ______________________________________________ DATE 1-4 ____________ PERIOD _____ Skills Practice Angle Measure For Exercises 1–12, use the figure at the right. U Name the vertex of each angle. 4 1. 4 S 2. 1 T 3 5 1 3. 2 W 4. 5 2V Name the sides of each angle. 5. 4 6. 5 7. STV 8. 1 Write another name for each angle. 9. 3 10. 4 12. 2 Measure each angle and classify it as right, acute, or obtuse. 13. NMP 14. OMN 15. QMN 16. QMO P Q O L M N and BC are opposite rays, ALGEBRA In the figure, BA bisects EBC, and BF bisects ABE. BD E F D 17. If mEBD 4x 16 and mDBC 6x 4, find mEBD. A B C 18. If mABF 7x 8 and mEBF 5x 10, find mEBF. © Glencoe/McGraw-Hill 21 Glencoe Geometry Lesson 1-4 11. WTS NAME ______________________________________________ DATE 1-4 ____________ PERIOD _____ Practice Angle Measure For Exercises 1–10, use the figure at the right. 6 Name the vertex of each angle. 1. 5 2. 3 3. 8 4. NMP 7 O 8 1 P Q 2 3 5 4 M N R Name the sides of each angle. 5. 6 6. 2 7. MOP 8. OMN Write another name for each angle. 9. QPR 10. 1 Measure each angle and classify it as right, acute, or obtuse. 11. UZW 12. YZW 13. TZW 14. UZT V W X U T Z Y and CD are opposite rays, ALGEBRA In the figure, CB bisects DCF, and CG bisects FCB. CE 15. If mDCE 4x 15 and mECF 6x 5, find mDCE. 16. If mFCG 9x 3 and mGCB 13x 9, find mGCB. 17. TRAFFIC SIGNS The diagram shows a sign used to warn drivers of a school zone or crossing. Measure and classify each numbered angle. D E C F G B 2 1 © Glencoe/McGraw-Hill 22 Glencoe Geometry NAME ______________________________________________ DATE 1-4 ____________ PERIOD _____ Reading to Learn Mathematics Angle Measure Pre-Activity How big is a degree? Read the introduction to Lesson 1-4 at the top of page 29 in your textbook. • A semicircle is half a circle. How many degrees are there in a semicircle? • How many degrees are there in a quarter circle? 1. Match each description in the first column with one of the terms in the second column. Some terms in the second column may be used more than once or not at all. a. a figure made up of two noncollinear rays with a 1. vertex common endpoint 2. angle bisector b. angles whose degree measures are less than 90 3. opposite rays c. angles that have the same measure 4. angle d. angles whose degree measures are between 90 and 180 5. obtuse angles e. a tool used to measure angles 6. congruent angles f. the common endpoint of the rays that form an angle 7. right angles g. a ray that divides an angle into two congruent angles 8. acute angles 9. compass 10. protractor 2. Use the figure to name each of the following. E a. a right angle F D b. an obtuse angle 28 28 C c. an acute angle d. a point in the interior of EBC A B G e. a point in the exterior of EBA f. the angle bisector of EBC g. a point on CBE h. the sides of ABF i. a pair of opposite rays j. the common vertex of all angles shown in the figure k. a pair of congruent angles l. the angle with the greatest measure Helping You Remember 3. A good way to remember related geometric ideas is to compare them and see how they are alike and how they are different. Give some similarities and differences between congruent segments and congruent angles. © Glencoe/McGraw-Hill 23 Glencoe Geometry Lesson 1-4 Reading the Lesson NAME ______________________________________________ DATE 1-4 ____________ PERIOD _____ Enrichment Angle Relationships Angles are measured in degrees (). Each degree of an angle is divided into 60 minutes (), and each minute of an angle is divided into 60 seconds ( ). 60 1 60 1 1 2 67 6730 70.4 70°24 90 89°60 Two angles are complementary if the sum of their measures is 90. Find the complement of each of the following angles. 1. 3515 2. 2716 3. 1554 4. 291822 5. 342945 6. 8723 Two angles are supplementary if the sum of their measures is 180. Find the supplement of each of the following angles. 7. 12018 8. 8412 10. 451624 11. 392154 12. 1291836 13. 985259 14. 9232 15. 123 © Glencoe/McGraw-Hill 9. 1102 24 Glencoe Geometry NAME ______________________________________________ DATE 1-5 ____________ PERIOD _____ Study Guide and Intervention Angle Relationships Pairs of Angles Adjacent angles are angles in the same plane that have a common vertex and a common side, but no common interior points. Vertical angles are two nonadjacent angles formed by two intersecting lines. A pair of adjacent angles whose noncommon sides are opposite rays is called a linear pair. Example Identify each pair of angles as adjacent angles, vertical angles, and/or as a linear pair. a. b. S T U R M 4 P 1 3N 2 S R SRT and TRU have a common vertex and a common side, but no common interior points. They are adjacent angles. c. d. D 5 A 1 and 3 are nonadjacent angles formed by two intersecting lines. They are vertical angles. 2 and 4 are also vertical angles. 60 6 B C 30 6 and 5 are adjacent angles whose noncommon sides are opposite rays. The angles form a linear pair. B A 120 F 60 G A and B are two angles whose measures have a sum of 90. They are complementary. F and G are two angles whose measures have a sum of 180. They are supplementary. Exercises Identify each pair of angles as adjacent, vertical, and/or as a linear pair. 2. 1 and 6 V 2 1 3. 1 and 5 4. 3 and 2 3 4 6Q R R S P For Exercises 5–7, refer to the figure at the right. 5. Identify two obtuse vertical angles. S 5 V N U 6. Identify two acute adjacent angles. T 7. Identify an angle supplementary to TNU. 8. Find the measures of two complementary angles if the difference in their measures is 18. © Glencoe/McGraw-Hill 25 Glencoe Geometry Lesson 1-5 1. 1 and 2 T U NAME ______________________________________________ DATE 1-5 ____________ PERIOD _____ Study Guide and Intervention (continued) Angle Relationships Perpendicular Lines Lines, rays, and segments that form four right angles are perpendicular. The right angle symbol indicates that the lines is perpendicular to are perpendicular. In the figure at the right, AC BD , or AC ⊥ BD . A B C D Example Find x so that D Z ⊥P Z . If DZ ⊥P Z , then mDZP 90. mDZQ mQZP (9x 5) (3x 1) 12x 6 12x x mDZP 90 90 84 7 D Q (9x 5) (3x 1) Sum of parts whole Substitution Z Simplify. P Subtract 6 from each side. Divide each side by 12. Exercises ⊥ MQ . 1. Find x and y so that NR N P 2. Find mMSN. 5x M x (9y 18) S Q R ⊥ BF . Find x. 3. mEBF 3x 10, mDBE x, and BD E 4. If mEBF 7y 3 and mFBC 3y 3, find y so ⊥ that EB BC . D F B A C 5. Find x, mPQS, and mSQR. P S 3x (8x 2) Q R 6. Find y, mRPT, and mTPW. T (4y 5) (2y 5) R P W V S © Glencoe/McGraw-Hill 26 Glencoe Geometry NAME ______________________________________________ DATE 1-5 ____________ PERIOD _____ Skills Practice Angle Relationships For Exercises 1–6, use the figure at the right and a protractor. E F 1. Name two acute vertical angles. K H 2. Name two obtuse vertical angles. G J 3. Name a linear pair. 4. Name two acute adjacent angles. 5. Name an angle complementary to EKH. 6. Name an angle supplementary to FKG. 7. Find the measures of an angle and its complement if one angle measures 18 degrees more than the other. 8. The measure of the supplement of an angle is 36 less than the measure of the angle. Find the measures of the angles. ALGEBRA For Exercises 9–10, use the figure at the right. R . 9. If mRTS 8x 18, find x so that TR ⊥ TS 10. If mPTQ 3y 10 and mQTR y, find y so that PTR is a right angle. Q P T Determine whether each statement can be assumed from the figure. Explain. S W V 11. WZU is a right angle. X Y Z U Lesson 1-5 12. YZU and UZV are supplementary. 13. VZU is adjacent to YZX. © Glencoe/McGraw-Hill 27 Glencoe Geometry NAME ______________________________________________ DATE 1-5 ____________ PERIOD _____ Practice Angle Relationships For Exercises 1–4, use the figure at the right and a protractor. G H F 1. Name two obtuse vertical angles. C B E 2. Name a linear pair whose vertex is B. A D 3. Name an angle not adjacent to but complementary to FGC. 4. Name an angle adjacent and supplementary to DCB. 5. Two angles are complementary. The measure of one angle is 21 more than twice the measure of the other angle. Find the measures of the angles. 6. If a supplement of an angle has a measure 78 less than the measure of the angle, what are the measures of the angles? ALGEBRA For Exercises 7–8, use the figure at the right. A B 7. If mFGE 5x 10, find x so that FC ⊥ AE . C G F 8. If mBGC 16x 4 and mCGD 2x 13, find x so that BGD is a right angle. D E Determine whether each statement can be assumed from the figure. Explain. N O 9. NQO and OQP are complementary. P Q M 10. SRQ and QRP is a linear pair. R S 12. STREET MAPS Darren sketched a map of the cross streets nearest to his home for his friend Miguel. Describe two different angle relationships between the streets. © Glencoe/McGraw-Hill 28 Be aco n 11. MQN and MQR are vertical angles. Olive Ma in Glencoe Geometry NAME ______________________________________________ DATE 1-5 ____________ PERIOD _____ Reading to Learn Mathematics Angle Relationships Pre-Activity What kinds of angles are formed when streets intersect? Read the introduction to Lesson 1-5 at the top of page 37 in your textbook. • How many separate angles are formed if three lines intersect at a common point? (Do not use an angle whose interior includes part of another angle.) • How many separate angles are formed if n lines intersect at a common point? (Do not count an angle whose interior includes part of another angle.) Reading the Lesson 1. Name each of the following in the figure at the right. 65 2 3 4 1 a. two pairs of congruent angles b. a pair of acute vertical angles c. a pair of obtuse vertical angles d. four pairs of adjacent angles e. two pairs of vertical angles f. four linear pairs g. four pairs of supplementary angles 2. Tell whether each statement is always, sometimes, or never true. a. If two angles are adjacent angles, they form a linear pair. b. If two angles form a linear pair, they are complementary. c. If two angles are supplementary, they are congruent. d. If two angles are complementary, they are adjacent. e. When two perpendicular lines intersect, four congruent angles are formed. f. Vertical angles are supplementary. g. Vertical angles are complementary. h. The two angles in a linear pair are both acute. i. If two angles form a linear pair, one is acute and the other is obtuse. 3. Complete each sentence. a. If two angles are supplementary and x is the measure of one of the angles, then the measure of the other angle is . Helping You Remember 4. Look up the nonmathematical meaning of supplementary in your dictionary. How can this definition help you to remember the meaning of supplementary angles? © Glencoe/McGraw-Hill 29 Glencoe Geometry Lesson 1-5 b. If two angles are complementary and x is the measure of one of the angles, then the measure of the other angle is . NAME ______________________________________________ DATE 1-5 ____________ PERIOD _____ Enrichment Curve Stitching The star design at the right was created by a method known as curve stitching. Although the design appears to contain curves, it is made up entirely of line segments. To begin the star design, draw a 60° angle. Mark eight equally-spaced points on each ray, and number the points as shown below. Then connect pairs of points that have the same number. 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 To make a complete star, make the same design in six 60° angles that have a common central vertex. 1. Complete the section of the star design above by connecting pairs of points that have the same number. 2. Complete the following design. 11 12 13 14 15 16 17 18 19 1 11 2 12 3 13 4 14 5 15 6 16 7 17 8 18 9 19 1 2 3 4 5 6 7 8 9 3. Create your own design. You may use several angles, and the angles may overlap. © Glencoe/McGraw-Hill 30 Glencoe Geometry NAME ______________________________________________ DATE 1-6 ____________ PERIOD _____ Study Guide and Intervention Polygons A polygon is a closed figure formed by a finite number of coplanar line segments. The sides that have a common endpoint must be noncollinear and each side intersects exactly two other sides at their endpoints. A polygon is named according to its number of sides. A regular polygon has congruent sides and congruent angles. A polygon can be concave or convex. Example Name each polygon by its number of sides. Then classify it as concave or convex and regular or irregular. a. D E b. F H L I G J The polygon has 4 sides, so it is a quadrilateral. It is concave because part of D E or E F lies in the interior of the figure. Because it is concave, it cannot have all its angles congruent and so it is irregular. K The figure is not closed, so it is not a polygon. d. c. The polygon has 5 sides, so it is a pentagon. It is convex. All sides are congruent and all angles are congruent, so it is a regular pentagon. The figure has 8 congruent sides and 8 congruent angles. It is convex and is a regular octagon. Exercises Name each polygon by its number of sides. Then classify it as concave or convex and regular or irregular. © 1. 2. 3. 4. 5. 6. Glencoe/McGraw-Hill 31 Glencoe Geometry Lesson 1-6 Polygons NAME ______________________________________________ DATE 1-6 ____________ PERIOD _____ Study Guide and Intervention (continued) Polygons Perimeter The perimeter of a polygon is the sum of the lengths of all the sides of the polygon. There are special formulas for the perimeter of a square or a rectangle. Example Write an expression or formula for the perimeter of each polygon. Find the perimeter. a. b. 4 in. b c 3 in. a 5 cm s 5 in. c. 5 cm s 3 ft s 5 cm 2 ft w s 5 cm Pabc 345 12 in. w P 2 2w 2(3) 2(2) 10 ft P 4s 4(5) 20 cm Exercises Find the perimeter of each figure. 1. 2. 3 cm 2.5 cm 5.5 ft square 3.5 cm 3. 4. 27 yd 19 yd 1 cm 14 yd 12 yd 24 yd Find the length of each side of the polygon for the given perimeter. 5. P 96 6. P 48 x 2x rectangle © x x2 x Glencoe/McGraw-Hill 2x 32 Glencoe Geometry NAME ______________________________________________ DATE 1-6 ____________ PERIOD _____ Skills Practice Name each polygon by its number of sides and then classify it as convex or concave and regular or irregular. 1. 2. 3. 4. 5. 6. Find the perimeter of each figure. 7. 8. 20 yd 9. 6m 4m 20 yd 18 yd 40 yd 3m 2m 5m 2 in. 2 in. 2 in. 10 in. 10 in. 2 in. 2 in. 2 in. COORDINATE GEOMETRY Find the perimeter of each polygon. 10. triangle ABC with vertices A(3, 5), B(3, 1), and C(0, 1) 11. quadrilateral QRST with vertices Q(3, 2), R(1, 2), S(1, 4), and T(3, 4) 12. quadrilateral LMNO with vertices L(1, 4), M(3, 4), N(2, 1), and O(2, 1) ALGEBRA Find the length of each side of the polygon for the given perimeter. 13. P 104 millimeters 14. P 84 kilometers 15. P 88 feet 4w 1 w © Glencoe/McGraw-Hill 33 Glencoe Geometry Lesson 1-6 Polygons NAME ______________________________________________ DATE 1-6 ____________ PERIOD _____ Practice Polygons Name each polygon by its number of sides and then classify it as convex or concave and regular or irregular. 1. 2. 3. Find the perimeter of each figure. 4. 7 mm 5. 18 mm 6. 21 mi 10 mm 18 mm 14 cm 2 cm 33 mi 6 cm 4 cm 6 cm 6 cm 4 cm 14 cm 32 mi COORDINATE GEOMETRY Find the perimeter of each polygon. 7. quadrilateral OPQR with vertices O(3, 2), P(1, 5), Q(6, 4), and R(5, 2) 8. pentagon STUVW with vertices S(0, 0), T(3, 2), U(2, 5), V(2, 5), and W(3, 2) ALGEBRA Find the length of each side of the polygon for the given perimeter. 9. P 26 inches 10. P 39 centimeters 11. P 89 feet 3x 5 6n 8 2x 2 2x 3 n x9 5x 4 SEWING For Exercises 12–13, use the following information. Jasmine plans to sew fringe around the scarf shown in the diagram. 12. How many inches of fringe does she need to purchase? 16 in. 4 in. 4 in. 16 in. 13. If Jasmine doubles the width of the scarf, how many inches of fringe will she need? © Glencoe/McGraw-Hill 34 Glencoe Geometry NAME ______________________________________________ DATE 1-6 ____________ PERIOD _____ Reading to Learn Mathematics Pre-Activity How are polygons related to toys? Read the introduction to Lesson 1-6 at the top of page 45 in your textbook. Name four different shapes that can each be formed by four sticks connected to form a closed figure. Assume you have sticks with a good variety of lengths. Reading the Lesson 1. Tell why each figure is not a polygon. a. b. c. 2. Name each polygon by its number of sides. Then classify it as convex or concave and regular or not regular. a. b. c. 3. What is another name for a regular quadrilateral? 4. Match each polygon in the first column with the formula in the second column that can be used to find its perimeter. (s represents the length of each side of a regular polygon.) a. regular dodecagon b. square i. P 8s ii. P 6s c. regular hexagon iii. P a b c d. rectangle iv. P 12s e. regular octagon f. triangle v. P 2 2w vi. P 4s Helping You Remember 5. One way to remember the meaning of a term is to explain it to another person. How would you explain to a friend what a regular polygon is? © Glencoe/McGraw-Hill 35 Glencoe Geometry Lesson 1-6 Polygons NAME ______________________________________________ DATE 1-6 ____________ PERIOD _____ Enrichment Perimeter and Area of Irregular Shapes Two formulas that are used frequently in mathematics are perimeter and area of a rectangle. Perimeter: P 2 2w Area: A w, where is the length and w is the width However, many figures are combinations of two or more rectangles creating irregular shapes. To find the area of an irregular shape, it helps to separate the shape into rectangles, calculate the formula for each rectangle, then find the sum of the areas. Example Find the area of the figure at the right. Separate the figure into two rectangles. A w A1 9 2 18 9m 2m 5m 3m A2 3 3 9 9m 18 9 27 1 2m The area of the irregular shape is 27 m2. 5m 2 3m Find the area and perimeter of each irregular shape. 1. 2. 1 in. 12 m 4 in. 4 in. 9m 7m 13 m 6m 2 in. 26 m 3. 6 cm 2 cm 4. 4 cm 7 ft 3 ft 4 cm 6 ft 2 ft 2 cm 4 cm 9 ft 4 ft 4 cm 8 cm For Exercises 5–8, find the perimeter of the figures in Exercises 1–4. 5. 6. 7. 8. 9. Describe the steps you used to find the perimeter in Exercise 1. © Glencoe/McGraw-Hill 36 Glencoe Geometry NAME 1 DATE PERIOD Chapter 1 Test, Form 1 SCORE Write the letter for the correct answer in the blank at the right of each question. 1. Name the geometric shape modeled by a pinhole in a wall. A. line segment B. plane C. line D. point B 2. Which is another name for line ? A. AB C. C 3. Name the intersection of lines and A. A C. C P A F B. BD D. P 2. m D E C G m. 3. B. B D. P 4. Name three points coplanar with point A. A. B, C, F B. E, F, G C. B, C, E D. B, D, G 5. Find the length of R S . A. 33 mm C. 35 mm 4. R B. 34 mm D. 36 mm 5. S cm 1 2 3 4 6. Find the precision for a measurement of 72 centimeters. A. 0.5 cm B. 0.1 cm C. 1 mm D. 0.5 mm 7. Find the length of B C . A. 12 cm C. 25 cm 6. B. 13 cm D. 38 cm 8. Use the number line to find MN. A. 5 C. 5 A 13 cm B C M B. 1 D. 10 9. Find the distance between points P and Q. A. 5 B. 7 C. 9 D. 25 5 4 3 2 1 0 1 © Glencoe/McGraw-Hill C. (0, 3) 37 2 3 y P 9. Q x O 10. Find the coordinates of the midpoint of P Q . 1 B. 0, 3 2 8. N For Questions 9 and 10, use the figure given at the right. 1 A. 2, 3 2 7. 25 cm 10. 1 D. 3, 0 2 Glencoe Geometry Assessments For Questions 2–4, use the figure given at the right. 1. NAME 1 DATE Chapter 1 Test, Form 1 PERIOD (continued) For Questions 11–13, use the figure at the right. E 11. Which point is the vertex of all the angles in this figure? A. A B. B C. C D. E 11. F C 50 B D A 12. What type of angle is ABC? A. acute angle B. right angle C. obtuse angle 13. Which is true? A. mEBF 140 B. mEBF 90 12. D. straight angle 13. C. mEBF 50 D. mEBF 40 14. For what value of x is ATK MJS if mATK 5x 4 and mMJS 8x 11? A. 29 B. 15 C. 10 D. 5 For Questions 15–17, use the figure at the right. 15. Which pair of angles are vertical angles? A. RST, TSU B. RSX, TSU C. TSU, USV D. RSX, XSW T 15. (10y 10) 5x U S 4x R X 16. Which angle is supplementary to USV ? A. TSU B. VSW C. RSV 17. Find x and y. A. x 10, y 12 14. W V 16. D. WSR 17. B. x 20, y 7 C. x 10, y 8 D. x 50, y 40 For Questions 18–20, use the figures below. 8 cm 25 cm 12 cm 18 cm 8 cm 15 cm 4 cm 8 cm 15 cm 12 cm Figure A 15 cm 25 cm 8 cm 15 cm Figure B 18. Which figure is not a polygon? A. Figure A B. Figure B 8 cm 18 cm 15 cm Figure C Figure D 18. C. Figure C 19. Find the perimeter of the convex pentagon. A. 46 cm B. 50 cm C. 61 cm D. Figure D 19. D. 72 cm 20. Suppose the length and width of the rectangle are doubled. What is its perimeter? A. 120 cm B. 92 cm C. 76 cm D. 46 cm 20. Bonus Each side of a square is 2x 6 yards long. If the B: perimeter of the square is 72 yards what is the value of x? © Glencoe/McGraw-Hill 38 Glencoe Geometry NAME 1 DATE PERIOD Chapter 1 Test, Form 2A SCORE Write the letter for the correct answer in the blank at the right of each question. 1. How many planes can be drawn through any three noncollinear points? A. 0 B. 1 C. 2 D. 3 For Questions 2 and 3, use the figure at the right. D 2. Which three points in the figure are collinear? A. A, B, D B. E, C, A C. A, B, C D. F, E, G A B 3. Name the intersection of the plane P and the plane that contains points B, C, and D. A. point B B. B D C. BC D. triangle BCD 5 A. 1 in. 16 7 C. 1 in. 16 G R 3 B. 1 in. 8 5 D. 1 in. 8 in. 1 1 2 1 C. ft 8 1 2 1 4 B. ft 6. Find the length of P Q . A. 50.9 cm B. 46.3 cm C. 25.7 cm D. 21.3 cm 2 5. D. 1 in. 6. 38.3 cm P Q 12.6 cm R 7. Find y if B is between A and C, AB is 2y, BC is 6y, and AC is 48. A. 24 B. 8 C. 6 D. 4 7. 8. Find the distance between P(2, 8) and Q(5, 3). A. 9 B. 18 C. 34 8. D. 170 9. Find the coordinates of the midpoint of L B if L(8, 5) and B(6, 2). 1 A. 1, 3 2 1 B. 2, 1 2 1 C. 7, 3 2 9. 1 D. 7, 1 2 10. Find the coordinates of T given that S is the midpoint of RT , R(4, 2), and S(6, 8). A. (14, 4) B. (16, 14) C. (2, 10) D. (1, 5) © 3. 4. S 5. Find the precision for a measurement of 18 feet. A. ft P E Glencoe/McGraw-Hill 39 10. Glencoe Geometry Assessments 2. F C 4. Find the length of R S . 1. NAME 1 DATE Chapter 1 Test, Form 2A PERIOD (continued) For Questions 11 and 12, use the figure at the right. G 11. What type of angle is ABC? A. acute angle B. right angle C. obtuse angle D. straight angle A B 11. E D F C 12. Use a protractor to measure the angles in the figure. Which segment is an angle bisector? A. G E B. B C C. ED 12. D. E F For Questions 13–17, use the figure at the right. 13. Find mFBD if FBD and DBE are complementary and mFBD is twice mDBE. A. 30 B. 45 C. 60 D. 90 14. Which pair of angles are supplementary? A. ABE, CBD B. ABC, ABD C. ABC, CBD 15. Which angle is a vertical angle to ABE? A. DBE B. CBD C. ABC 16. If mCBF 6x 18, find x so that CB ⊥ BF. A. 90 B. 45 C. 18 C A 13. F B D E 14. D. ABC, EBD 15. D. EBA 16. D. 12 17. Find mABC if mABC 4x 9 and mEBD 7x 9. A. 6 B. 33 C. 45 D. 73 17. For Questions 18 and 19, use the figure at the right. (x 3) km 18. Which describes this figure? A. hexagon, concave, not regular B. pentagon, concave, regular C. hexagon, convex, not regular D. not a polygon 19. What is x for a perimeter of 108 kilometers? A. 53 B. 15 C. 18 19. D. 105 20. A rectangle has a length of 1.4 feet and a width of 1.2 feet. What is the effect on the perimeter of this rectangle if the length and width are doubled? A. The perimeter is doubled. B. The perimeter is increased by 8. C. The perimeter is multiplied by 4. D. The perimeter is tripled. Bonus Find mA if A is complementary to B, B is supplementary to C, mB 15x 2, and mC 25x 22. © Glencoe/McGraw-Hill 40 18. 20. B: Glencoe Geometry NAME 1 DATE PERIOD Chapter 1 Test, Form 2B SCORE Write the letter for the correct answer in the blank at the right of each question. 1. Suppose A and B are points. How many lines contain both A and B? A. 0 B. 1 C. 2 D. 3 1. A 2. Which three points in the figure are collinear? A. C, D, F B. B, C, D C. A, E, F D. A, D, E C 11 16 9 C. 1 in. 16 A. 1 in. B F 3. Name the intersection of the plane that contains points A, B, and D and the plane P. A. point D B. A D C. triangle BCD D. BD 4. Find the length of X Y . 2. 3. D E X 5 8 1 D. 1 in. 2 4. Y B. 1 in. in. 1 2 5. Find the precision for a measurement of 34.0 centimeters. A. 0.5 cm B. 1 mm C. 0.5 mm D. 1 cm 5. 6. Find the length of H J . A. 11.3 cm C. 13.7 cm 6. 29.1 cm B. 12.3 cm D. 45.9 cm G 16.8 cm H J 7. Find x if S is between R and T, RS is x 3, ST is 5x, and RT is 57. A. 9 B. 10 C. 10.8 D. 12 7. 8. Find the distance between M(2, 3) and N(8, 2). 8. A. 8 B. 61 D. 101 C. 10 9. Find the coordinates of the midpoint of A S if A(4, 7) and S(5, 3). A. (1, 10) 1 B. 4, 2 2 1 C. , 5 2 9. 1 D. , 5 2 10. Find the coordinates of T given that S is the midpoint of RT , R(2, 6), and S(2, 0). A. (6, 12) B. (6, 6) C. (0, 3) D. (2, 3) © P Glencoe/McGraw-Hill 41 10. Glencoe Geometry Assessments For Questions 2 and 3, use the figure at the right. NAME 1 DATE Chapter 1 Test, Form 2B PERIOD (continued) For Questions 11 and 12, use the figure at the right. D B 11. What type of angle is BAC? A. acute angle B. right angle C. obtuse angle D. straight angle C E 12. Use a protractor to measure the angles in the figure. Which segment is an angle bisector? A. A B B. C D C. CB 11. F A 12. D. A E For Questions 13–17, use the figure at the right. 13. Find mVSW if WSR and VSW are complementary and mWSR is four times mVSW. A. 72 B. 36 C. 22.5 D. 18 14. Which pair of angles are supplementary? A. USV, VSW B. VSW, WSR C. TSV, VSW 15. Which angle is a vertical angle to UST? A. VSW B. USV C. TSR 16. If mVSR 8x 18, find x so that US ⊥V S . A. 9 B. 12.25 C. 72 V W S U 13. R T 14. D. TSR, USW 15. D. WSR 16. D. 90 17. Find mUSW if mUSW 7x 34 and mTSR 4x 29. A. 147 B. 113 C. 84 D. 21 17. For Questions 18 and 19, use the figure at the right. y5 18. Which describes this figure? A. hexagon, convex, regular B. pentagon, concave, regular C. pentagon, convex, not regular D. not a polygon 19. What is y for a perimeter of 100 feet? A. 5 B. 15 y 19. C. 17 D. 23 20. A square has sides with a length of 5.8 inches. What is the effect on the perimeter of this square if the sides are tripled? A. The perimeter stays the same. B. The perimeter is increased by 12. C. The perimeter is multiplied by 3. D. The perimeter is multiplied by 9. Bonus Find mA if A is supplementary to B, B is supplementary to C, mB 12x 8, and mC 8x 8. © Glencoe/McGraw-Hill 18. 42 20. B: Glencoe Geometry NAME PERIOD Chapter 1 Test, Form 2C For Questions 1–4, use the figure at the right. P C A 1. What is another name for line ? SCORE B 1. D E 2. Name three points on plane P. 2. F 3. Name the intersection of planes N P and N. 3. 4. Name three noncoplanar points. For Questions 5 and 6, use the figure at the right. 4. A cm Assessments 1 DATE B 1 2 3 4 5 6 5. What is the length of B A ? 5. 6. What is the precision of your measurement of A B ? 6. 7. Find the length of D E if D is between points C and E, CD 6.5 centimeters, and CE 13.8 centimeters. 7. 8. Find the length of X Z . 8. 4x 3 2x 7 X 8 cm Y 9. Find x if R S S T . Z 9. 52 in. R 6x 8 S For Questions 10–12, use the coordinate grid. T y B 10. Find the distance between A and B. 10. A x O 11. Find the coordinates of the midpoint of C D . C 11. D 12. Find the coordinates of a point E if C is the midpoint of A E . 12. 13. The vertices of a triangle are located at P(0, 0), Q(8, 6), and R(3, 4). What is the perimeter of this triangle? 13. 14. Find x and y if U V bisects T W and UV 40. 14. U 3y 1 3x 2 3y 1 Z T 2y 6 W V © Glencoe/McGraw-Hill 43 Glencoe Geometry NAME 1 DATE Chapter 1 Test, Form 2C 15. Measure PQR. Then classify PQR as right, acute, or obtuse. (continued) 15. P Q R and EB are opposite In the figure, EA bisects FEG. rays and EC F 16. Find x if mFEG 82, and mFEC 5x 11. PERIOD C G 16. A E B D 17. If mAED 16y 10, find y so that D E ⊥A B . 17. For Questions 18–21, use the figure at the right. 1 72 (8y 16) 2 40 18. Find y. (11x 24) 19. Find m1. 18. 19. 20. Find m2. 20. 21. Find x . 21. For Questions 22–25, use the polygons at the right. 22. Name polygon ABCDEF by its sides. Then classify it as convex or concave and regular or not regular. B C R 6x 5 A 3y 1 D F E T 2y 11 22. S 23. Find the perimeter of polygon ABCDEF for x 4. 23. 24. Find the length of each side of polygon RST. 24. 25. Find the length of one side of a regular pentagon whose perimeter is the same as the perimeter of RST. 25. Bonus Find the dimensions of a rectangle whose length is 3 more than twice its width and has a perimeter of 30 centimeters. B: © Glencoe/McGraw-Hill 44 Glencoe Geometry NAME 1 DATE PERIOD Chapter 1 Test, Form 2D SCORE For Questions 1–4, use the figure at the right. 2. Name three points on plane R X m? Y B. 1. T U B S Z 2. V A m A and B. 3. Name the intersection of planes 3. 4. 4. Name three noncollinear points. For Questions 5 and 6, use the figure at the right. R ? 5. What is the length of Q Assessments 1. What is another name for line Q R in. 1 2 5. 6. What is the precision of your measurement of Q R ? 6. 7. Find the length of L O if O is between points L and M, LM 18.6 centimeters, and OM 12.9 centimeters. 7. 8. Find the length of D E . 8. 24 cm 3x 5 D E 5x 13 F 9. Find y if X Y Y Z . X Y 23 in. For Questions 10–12, use the coordinate grid. 10. Find the distance between L and M. 9. 5y 11 Z y M 10. x O P L N 11. 12. Find the coordinates of a point Q if P is the midpoint of N Q . 12. 13. The vertices of a triangle are located at P(0, 6), Q(8, 12), and R(3, 3). What is the perimeter of this triangle? 13. 14. Find x if R S bisects A B and RS 36. 14. 11. Find the coordinates of the midpoint of M N . R 18 25 3x A 2y 5 T B 2y 6 S © Glencoe/McGraw-Hill 45 Glencoe Geometry NAME 1 DATE Chapter 1 Test, Form 2D 15. Measure ABC. Then classify ABC as right, acute, or obtuse. PERIOD (continued) 15. A B and RD are opposite In the figure, RC bisects WRV. rays and RQ C P (13x 12) C 16. Find y if mWRQ 48 and mQRV 7y 6. R 16. D W V Q 17. Find x so that C R ⊥P R . 17. For Questions 18–21, use the figure at the right. 2 (9x 5) 18. Find x. (7y 27) 1 58 18. 19. Find m1. 19. 20. Find m2. 20. 21. Find y. 21. For Questions 22–25, use the polygons at the right. S R A B 27 4x T 22. Name polygon RSTUV 5y 8 by its sides. Then V U classify it as convex or concave and regular or not regular. D 8x 3 22. C 23. Find the perimeter of polygon RSTUV for y 9. 23. 24. Find the length of each side of polygon ABCD. 24. 25. Find the length of the sides of a regular triangle whose perimeter is the same as the perimeter of ABCD. 25. Bonus Find the lengths of the sides of a triangle whose perimeter is 37. The measure of the first side of the triangle is 8 less than the second side, and the second side is twice the length of the third side. B: © Glencoe/McGraw-Hill 46 Glencoe Geometry NAME PERIOD Chapter 1 Test, Form 3 For Questions 1–3, use the figure at the right. SCORE B C 1. Name five planes shown in the figure. 1. F A E D P 2. 2. Name a line that is coplanar with . AD and AB 3. Name the intersection of plane points A, B, and E. P and the plane that contains For Questions 4 and 5, use the figure at the right. B . 4. Find the length of A A in. Assessments 1 DATE 3. B 6 4. 7 5. Find the precision for the measurement of A B . 5. 6. Find two possible lengths for C D if C, D, and E are collinear, CE 15.8 centimeters, and DE 3.5 centimeters. 6. 7. Find the length of R S if S is between R and T, the length of 1 S R is the length of R T , RS 3x 3, and ST 2x 6. 7. 8. Find y if AC 3y 5, CB 4y 1, AB 9y 12, and point C lies between A and B. 8. 3 For Questions 9–11, use the coordinate grid at the right. y B 9. 9. Find the distance between A and B. O x A 10. Find two possible coordinates of a point 1 D on a line containing A B so that AD AB. 10. 11. Find two values of y for C located at (1, y) and AC 5. 11. 4 © Glencoe/McGraw-Hill 47 Glencoe Geometry NAME 1 DATE Chapter 1 Test, Form 3 PERIOD (continued) 12. Find y if S is the midpoint of R T , T is the midpoint of R U , RS 6x 5, ST 8x 1, and TU 11y 13. 12. 13. Find all values of x that will make A an obtuse angle given mA 12x 6. 13. bisects RSU and 14. Find mRST if ST bisects TSV. SU 14. R (x 2y 1) T (6x 9) S (2y 5) U V 15. Find m1 if 1 is complementary to 2, 2 is supplementary 15. to 3, and m3 126. ⊥ XZ , Y is in the interior of WXZ, 16. Find y if XW mWXY 6y 3, and mYXZ 4y 13. 16. is the 17. Find the length of L M if ON bisector of L M and LN 3x 2. 17. O 7x 1 L N M For Questions 18 and 19, use the coordinate grid. 18. Graph polygon ABCD with vertices A(4, 3), B(0, 3), C(2, 2), and D(5, 6). Then name polygon ABCD by its number of sides and classify it as convex or concave and regular or irregular. 18. 19. Find the perimeter of polygon ABCD. 19. 20. Find the perimeter of regular triangle DEF if DE 28 3y and EF 2y 3. 20. Bonus Suppose a regular quadrilateral and a regular triangle have B: the same perimeter. The sides of the triangle are 3 inches longer than the sides of the quadrilateral. Find the lengths of the sides of the quadrilateral and the triangle. © Glencoe/McGraw-Hill 48 Glencoe Geometry NAME 1 DATE Chapter 1 Open-Ended Assessment PERIOD SCORE Demonstrate your knowledge by giving a clear, concise solution to each problem. Be sure to include all relevant drawings and justify your answers. You may show your solution in more than one way or investigate beyond the requirements of the problem. 1. Draw and label a figure that shows that plane R contains both lines s and that intersect at point B. Name three collinear points in plane R . AC Assessments 2. Draw a line on a coordinate plane so that you can determine at least two points on the graph. Label those two points D and G. a. Find the distance between points D and G. b. Find the coordinates of E, the midpoint of D G . c. Find the coordinates of point H given that G is the midpoint of D H . 3. Rectangle WXYZ has a length that is 5 more than three times its width. a. Draw and label a figure for rectangle WXYZ. b. Write an algebraic expression for the perimeter of the rectangle. c. Find the width if the perimeter is 58 millimeters. Explain how you can check that your answer is correct. d. Use a ruler to draw and label P Q , which is congruent to the segment representing the length of rectangle WXYZ. What is the measure of P Q ? e. Explain how to find the precision of the measurement of P Q . 4. Draw an acute angle, ABC. Let mABC 6x 1. a. Use a protractor to determine the measure of ABC. Use this measure to determine the value of x. b. Explain how you would determine the measure of an angle that is complementary to ABC. c. Explain how you would determine the measure of an angle that is supplementary to ABC. is in the interior of TRU, mTRS 4x 6, and mSRU 8x 6. 5. RS . a. Draw TRU and RS an angle bisector. Explain b. Determine the value of x that will make RS your steps. and RT when x 7.5. c. Describe the relationship between RU © Glencoe/McGraw-Hill 49 Glencoe Geometry NAME 1 DATE PERIOD Chapter 1 Vocabulary Test/Review convex coplanar degree distance exterior interior line line segment linear pair midpoint acute angle adjacent angles angle angle bisector betweenness collinear complementary concave congruent construction SCORE regular polygon relative error right angle segment bisector sides space supplementary undefined terms vertex vertical angles n-gon obtuse angle opposite rays perimeter perpendicular plane point polygon precision ray Choose from the terms above to complete each sentence. 1. Two lines are ? 2. Two angles are if they intersect to form a right angle. 1. if their measures have a sum of 90°. 2. ? ? 3. When two rays intersect with a common endpoint a(n) is formed. ? 4. The is the point located halfway between the endpoints of a segment. 5. 4. ? are nonadjacent angles formed by the intersection of two lines. 6. A(n) ? divides an angle into two congruent angles. 7. Two angles are ? 9. A(n) ? ? if is an angle whose measure is less than 90°. 10. Two segments are ? 5. 6. if their measures have a sum of 180°. 8. Two angles that lie in the same plane are called they share a common side and a common vertex. 3. if they have the same measure. 7. 8. 9. 10. In your own words— 11. Explain how to find the precision of a measurement of 1 5 inches on a ruler marked in half inches. 11. 12. Describe what is meant by betweenness of points using collinear points M, P, and Q. 12. 2 © Glencoe/McGraw-Hill 50 Glencoe Geometry NAME 1 DATE PERIOD Chapter 1 Quiz SCORE (Lessons 1–1 and 1–2) For Questions 1–3, use the figure at the right. 1. What is another name for line ? S V 2. Name the intersection of lines and m T R U m. 2. 3. Name three collinear points. 3. A B . 4. Find the length of A B in. 4. 1 5. Find the precision of the measurement of A B . 5. 6. Find the length of U W if W is between U and V, UV 16.8 centimeters, and VW 7.9 centimeters. 6. 7. Find x if RS 24 centimeters. 6x 4 R 7. 10 cm T S 8. Find the length of L O if M is between L and O, LM 7x 9, MO 14 inches, and LO 10x 7. 8. 9. Find x if P Q R S , PQ 9x 7, and RS 29. 9. 10. STANDARDIZED TEST PRACTICE Which of the following is not an undefined term in geometry? A. plane B. point C. bisector D. line NAME 1 Assessments For Questions 4 and 5, use the figure at the right. 1. 10. DATE PERIOD Chapter 1 Quiz SCORE (Lesson 1–3) A B for A(2, 5) and B(6, 9). 1. Find the coordinates of the midpoint of 1. 2. Find the coordinates of D if E is the midpoint of C D , for C(3, 4) and E(0, 1). 2. 3. What is the length of F H if G is the midpoint, FG 12x 5, and GH 7x? W 4. What is the length of U V if WX is the segment bisector of U V at point Z? V 6x 8 3. 4. Z 9x 2 U X 5. STANDARDIZED TEST PRACTICE Find the distance between A(2, 1) and B(4, 3). A. 52 B. 52 C. 20 D. 8 © Glencoe/McGraw-Hill 51 5. Glencoe Geometry NAME 1 DATE PERIOD Chapter 1 Quiz SCORE (Lessons 1–4 and 1–5) For Questions 1–6, use the figure at the right. U 1. Name the vertex of 1. 2. Classify TSV as right, acute, or obtuse. W S T 3. Name a point in the exterior of RTS. V 1 2. P R 3. 4. Find mTSU if S U bisects TSV, mTSU 4y 11, and mUSV 6y 5. 4. 5. Name a pair of adjacent angles. 5. 6. Name a pair of vertical angles. A 7. Find mDBC if mABC 5x 3 and ABD DBC. For Questions 8 and 9, lines adjacent angles 1 and 2. (3x 2) B D C 6. 7. p and q intersect to form 8. If m1 7x 6 and m2 8x 6, find x so that perpendicular to q. p is 8. 9. If m1 4x 3 and m2 3x 8, find x so that 1 is supplementary to 2. 9. 10. STANDARDIZED TEST PRACTICE The difference between two complementary angles is 14. Which is the measure of one of those angles? A. 14 B. 52 C. 83 D. 90 NAME 1 1. 10. DATE PERIOD Chapter 1 Quiz SCORE (Lesson 1–6) 1. Draw a concave pentagon. 1. 2. Find the length of each side of a regular hexagon whose perimeter is 84 meters. 2. 3. If x 5, find the perimeter of the rectangle whose length is 6x 4 and whose width is 3x 2. 3. 4. The perimeter of a convex pentagon is 15 feet. What is the effect on its perimeter if each side is doubled? 4. 5. For what value of y is triangle ABC a regular triangle? 5. B 9y 4 A © Glencoe/McGraw-Hill 52 5y 20 7y 12 C Glencoe Geometry NAME 1 DATE PERIOD Chapter 1 Mid-Chapter Test SCORE (Lessons 1–1 through 1–3) Part I Write the letter for the correct answer in the blank at the right of each question. For Questions 1 and 2, use the figure at the right. E 1. Which point is coplanar with points A and C? A. A B. B C. C D. D A 1. M B C For Questions 3 and 4, use the figure at the right. D. M A B ? 3. What is the length of A 1 A. about 1 in. 4 3 C. about 1 in. 4 2. B in. 1 2 D. about 2 in. 4. What is the precision for the measurement of A B ? A. 1 in. 3. 1 B. about 1 in. 2 1 B. in. 2 5. What is the length of T S ? A. 9.4 cm C. 4.7 cm 4. 1 C. in. 4 1 D. in. 8 5. 8.9 cm B. 8.9 cm D. 4.2 cm R 4.7 cm T S Part II For Questions 6–8, use the coordinate grid. y R U S 6. Find the distance between R and S. 6. x O 7. Find the coordinates of the midpoint of T U . 7. T 8. Find the coordinates of a point M given that U is the midpoint of M S . 8. 9. Find y if M is the midpoint of L N . L 10. In the figure, WZ bisects X Y . Find the length of X Y . 9. 6y 5 9y 4 M N 10. W X V 6x 11 4x 5 Y Z © Glencoe/McGraw-Hill 53 Glencoe Geometry Assessments D . 2. Name the point of intersection of plane M and DE A. D B. E C. B NAME 1 DATE PERIOD Chapter 1 Cumulative Review SCORE (Chapter 1) For Questions 1 and 2, use the figure at the right. A 1. Name three points that are collinear. C B D H G (Lesson 1-1) 1. F 2. Name the intersection of AE and CG . E 2. (Lesson 1-1) Find the measurement of each segment. Assume that the art is not drawn to scale. (Lesson 1-2) 3. A B A 3. B 2 cm C 5 cm 4. K N J K 4 mm L M 4. N 3 mm 5. Use the Pythagorean Theorem to find the distance between A(12, 13) and B(2, 11). (Lesson 1-3) 5. 6. Find the coordinates of B if A has coordinates (3, 5) and Y(2, 3) is the midpoint of A B . (Lesson 1-3) 6. For Questions 7 and 8, use the figure to name the vertex and sides of each angle. Then measure and classify each angle. (Lesson 1-4) 7. JNK K L 77 J N 157 H 26 7. M 8. HNK For Questions 9–11, use the figure at the right. (Lesson 1-5) 9. Name a pair of supplementary nonadjacent angles. 8. B C 120 60 A 30 F D G 9. E 10. Name two obtuse vertical angles. 10. 11. Name an angle complementary to CFD. 11. 12. If mHJK 7y 2 and mPQR 133, find y so that HJK is supplementary to PQR. (Lesson 1-5) 12. 13. Name this polygon by its number of sides and then classify it as convex or concave and regular or irregular. (Lesson 1-6) 13. 14. Find the perimeter of ABC if A(1, 1), B(4, 3), and C(3, 2). 14. (Lesson 1-6) 15. Find the length of each side of a regular pentagon whose perimeter is 90 centimeters. (Lesson 1-6) © Glencoe/McGraw-Hill 54 15. Glencoe Geometry NAME 1 DATE PERIOD Standardized Test Practice SCORE (Chapter 1) Part 1: Multiple Choice Instructions: Fill in the appropriate oval for the best answer. 1. A B C D 2. E F G H 3. What is the precision of a measurement of 49.5 centimeters on a ruler with millimeter marks? (Lesson 1-2) A. 49 cm to 50 cm B. 49.0 cm to 50.0 cm C. 490 mm to 500 mm D. 494.5 mm to 495.5 mm 3. A B C D 4. When segments have the same measure, they are said to be ? . (Lesson 1-2) E. accurate F. congruent G. precise H. constructed 4. E F G H 5. Find the distance between A(3, 5) and B(4, 2), to the nearest hundredth. (Lesson 1-3) A. 6.75 B. 7.62 C. 8.06 D. 10 5. A B C D 6. Find EF if E is the midpoint of DF , DE 15 3x, and EF x 3. (Lesson 1-3) E. 1 F. 3 G. 6 H. 9 6. E F G H 7. A B C D 8. E F G H 9. A B C D 10. E F G H (Lesson 1-1) C. a meter stick D. a diskette 2. Which figure shows AB and point G contained in plane R ? (Lesson 1-1) E. F. A B G R G A G. B R H. G A A B R G R B For Questions 7–9, use the figure. 7. What is another name for 2? A. WYX B. WXY C. 3 D. Y W 5 2 (Lesson 1-4) 8. Which angles form a linear pair? E. 1 and 3 F. 2 and 5 4 3 Y 1 X (Lesson 1-5) G. 2 and 3 9. Name the angle that is vertical to 3. (Lesson 1-5) A. 1 B. 2 C. 3 H. 1 and 4 D. 4 10. Find the length of one side of a regular hexagon whose perimeter is 75 feet. (Lesson 1-6) E. 25 ft F. 18.75 ft G. 15 ft H. 12.5 ft © Glencoe/McGraw-Hill 55 Glencoe Geometry Assessments 1. Which object models a line? A. a fly B. a wall NAME 1 DATE Standardized Test Practice PERIOD (continued) Part 2: Grid In Instructions: Enter your answer by writing each digit of the answer in a column box and then shading in the appropriate oval that corresponds to that entry. 11. How many points name a line? 12. What is the measure of A C ? 3.7 A 11. (Lesson 1-1) (Lesson 1-2) B C K G 2 1 . / . / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 5.2 bisects KHI and For Questions 13–15, HL and HI are opposite rays. HG J 12. 2 L 13. 3 4 H I 13. If 1 2, mKHG 70, and m1 3d 2, find d. (Lesson 1-4) 14. If m2 a 15 and m3 a 35, find a so ⊥ HJ . (Lesson 1-5) that HL 15. Find m4, if mGHL 125. (Lesson 1-5) 15. 14. 1 1 . / . / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 8 . 9 . / . / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 2 0 . / . / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 5 5 . / . / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 Part 3: Short Response Instructions: Show your work or explain in words how you found your answer. 16. Find the length of X Z if Y(4, 4) is the midpoint of X Z and X has coordinates (2, 4). (Lesson 1-3) 17. Find the perimeter of this hexagon. 16. 17. 30 m 7m (Lesson 1-6) 6m 8.5 m 18. Find the measure of W X , if the perimeter of pentagon UVWXY is 48 units. (Lesson 1-6) V 20 m 10 m 18. U 10 a Y 2a W © Glencoe/McGraw-Hill 56 4a 7 X Glencoe Geometry NAME 1 DATE PERIOD Standardized Test Practice Student Record Sheet (Use with pages 58–59 of the Student Edition.) Part 1 Multiple Choice Select the best answer from the choices given and fill in the corresponding oval. 1 A B C D 4 A B C D 7 A B C D 2 A B C D 5 A B C D 8 A B C D 3 A B C D 6 A B C D 9 A B C D Part 2 Short Response/Grid In Solve the problem and write your answer in the blank. For Questions 14 and 15, also enter your answer by writing each number or symbol in a box. Then fill in the corresponding oval for that number or symbol. 14 11 12 13 14 (grid in) 15 (grid in) 15 . / . / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 . / . / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 Answers 10 Part 3 Open-Ended Record your answers for Questions 16–17 on the back of this paper. © Glencoe/McGraw-Hill A1 Glencoe Geometry © ____________ PERIOD _____ Points, Lines, and Planes Study Guide and Intervention Glencoe/McGraw-Hill Use the figure to name each of the following. A2 Exercises D or E m ? BD Q. Q for each relationship. m. E B Glencoe/McGraw-Hill 10. Line ᐉ contains points X and Y. 1 9. Point Y is not collinear with points T and P. 8. Point X is collinear with points A and P. at P. 7. ST intersects AB is in plane 6. AB Draw and label a plane 5. Name a point not on line ᐉ or line 4. Name the intersection of AC and DB . 3. Name a point not on AC . 2. What is another name for line , AC , BC , or 1. Name a line that contains point A. AB Refer to the figure. © N ᐉ A Q A T P S m A X E B D C Y C ᐉ B B D P Glencoe Geometry Answers for Exercises 6–10 ᐉ ᐉ The plane can be named as plane N or can be named using three noncollinear points in the plane, such as plane ABD, plane ACD, and so on. b. a plane containing point D The line can be named as ᐉ. Also, any two of the three points on the line can be used to name it. AC , or BC AB , a. a line containing point A Example In geometry, a point is a location, a line contains points, and a plane is a flat surface that contains points and lines. If points are on the same line, they are collinear. If points on are the same plane, they are coplanar. Name Points, Lines, and Planes 1-1 NAME ______________________________________________ DATE O. F or J © M andN intersect in HJ . Glencoe/McGraw-Hill 9. Line t contains point H and line plane N. M , and lines r and s 2 N F G N P t J C D H A I D J D M E A H E A B B s C O N r C B Glencoe Geometry Answers for Exercises 7–9 t does not lie in plane M or 8. Line r is in plane N , line s is in plane intersect at point J. 7. Planes Draw and label a figure for each relationship. 6. Name a point coplanar with D, C, and E. No; B, G, and H lie in plane BGH, but E does not. 5. Are points B, E, G, and H coplanar? Explain. 4. How many planes are shown in the figure? 6 Refer to the figure. plane N , plane ABC, plane ABD, plane EBC, plane EBD 3. Name three collinear points. A, B, E 2. Name a plane that contains point B. 1. Name a line that is not contained in plane Refer to the figure. Exercises Yes. They are contained in plane N. AB N , plane O, and plane P. b. Are points A, B, and D coplanar? There are three planes: plane a. How many planes appear in the figure? Example all points. It contains lines and planes. Space is a boundless, three-dimensional set of Points, Lines, and Planes (continued) ____________ PERIOD _____ Study Guide and Intervention Points, Lines, and Planes in Space 1-1 NAME ______________________________________________ DATE Answers (Lesson 1-1) Glencoe Geometry Lesson 1-1 © Points, Lines, and Planes Skills Practice Glencoe/McGraw-Hill n and p. C D p A A3 R T C P H U © Glencoe/McGraw-Hill 3 Yes; points A, B, and C lie in plane W. 12. Are points A, B, and C coplanar? Explain. A, B, E, F or B, C, D, E or A, C, D, F 11. Name four points that are coplanar. 2 q Z f A F B E W Glencoe Geometry C D f intersect at point Z s J contains line s. 8. Lines q and in plane U. J 6. Plane 10. How many of the planes contain points F and E? 5 9. How many planes are shown in the figure? Refer to the figure. B Y lies in plane B and contains 7. YP point C, but does not contain point H. K 5. Point K lies on RT . n G B ____________ PERIOD _____ Draw and label a figure for each relationship. Sample answers are given. Sample answer: plane G 4. Name the plane containing lines or DC CD 3. What is another name for line p ? A or B 2. Name a point contained in line n. p or CD 1. Name a line that contains point D. Refer to the figure. 1-1 NAME ______________________________________________ DATE (Average) Points, Lines, and Planes Practice S R M T N Q g C M K G S, X, M L O y N M q A x M W S X T plane and line STOP Glencoe Geometry Glencoe/McGraw-Hill Answers © line and point 12. a car antenna 9. 10. point tip of pin 4 plane 13. a library card 11. lines R Q N P Glencoe Geometry strings VISUALIZATION Name the geometric term(s) modeled by each object. No; sample answer: points N, R, and S lie in plane A, but point W does not. 8. Are points N, R, S, and W coplanar? Explain. 7. Name three collinear points. h 5. A line contains L(⫺4, ⫺4) and M(2, 3). Line q is in the same coordinate plane but does . Line q contains point N. not intersect LM 6. How many planes are shown in the figure? 6 Refer to the figure. T A and CG intersect at point M 4. AK in plane T. Draw and label a figure for each relationship. Sample answers are given. S P j ____________ PERIOD _____ . Sample answer: plane 3. Name the plane that contains TN and QR j or MT 2. Name a line that intersects the plane containing points Q, N, and P. , TN , NP g, TP 1. Name a line that contains points T and P. Refer to the figure. 1-1 NAME ______________________________________________ DATE Answers (Lesson 1-1) Lesson 1-1 © Glencoe/McGraw-Hill A4 plane c. There is exactly one d. There is exactly one Q P A R ᐉ m P D m B n ᐉ Glencoe/McGraw-Hill 5 Glencoe Geometry Sample answer: The prefix co- means together. The word collinear contains the word line, so collinear means together on a line. 4. Recall or look in a dictionary to find the meaning of the prefix co-. What does this prefix mean? How can it help you remember the meaning of collinear? Helping You Remember 3. Complete the figure at the right to show the following relationship: Lines ᐉ, m, and n are coplanar and lie in plane Q. Lines ᐉ and m intersect at point P. Line n intersects line m at R, but does not intersect line ᐉ. e. Line ᐉ lies in plane ACB. true U. false m is point P. true m do not intersect. false C U through any three noncollinear points. d. Points A, P,and B can be used to name plane c. Line ᐉ and line b. The intersection of plane ABC and line a. Points A, B, and C are collinear. false noncoplanar points. points. through any two points. 2. Refer to the figure at the right. Indicate whether each statement is true or false. line b. Points that do not lie in the same plane are called a. Points that lie on the same lie are called 1. Complete each sentence. collinear answer: It may not be possible to place the paper to touch all four points. • How will your answer change if there are four pencil points? Sample • How many ways can you do this if you keep the pencil points in the same position? one • Find three pencils of different lengths and hold them upright on your desk so that the three pencil points do not lie along a single line. Can you place a flat sheet of paper or cardboard so that it touches all three pencil points? yes Read the introduction to Lesson 1-1 at the top of page 6 in your textbook. Why do chairs sometimes wobble? Points, Lines, and Planes Reading the Lesson © ____________ PERIOD _____ Reading to Learn Mathematics Pre-Activity 1-1 NAME ______________________________________________ DATE Enrichment © 4. Make the capital letter O so that it extends to each side of the matrix. 2. Draw two lines that cross but have no common points. ____________ PERIOD _____ Glencoe/McGraw-Hill 6 Glencoe Geometry 5. Using separate grid paper, make dot designs for several other letters. Which were the easiest and which were the most difficult? See students’ work. 3. Make the number 0 (zero) so that it extends to the top and bottom sides of the matrix. 1. Draw two intersecting lines that have four points in common. Draw points on each matrix to create the given figures. Answers may vary. Sample answers are shown. Dot-matrix printers for computers used dots to form characters. The dots are often called pixels. The matrix at the right shows how a dot-matrix printer might print the letter P. A matrix is a rectangular array of rows and columns. Points and lines on a matrix are not defined in the same way as in Euclidean geometry. A point on a matrix is a dot, which can be small or large. A line on a matrix is a path of dots that “line up.” Between two points on a line there may or may not be other points. Three examples of lines are shown at the upper right. The broad line can be thought of as a single line or as two narrow lines side by side. Points and Lines on a Matrix 1-1 NAME ______________________________________________ DATE Answers (Lesson 1-1) Glencoe Geometry Lesson 1-1 © ____________ PERIOD _____ Linear Measure and Precision Study Guide and Intervention Glencoe/McGraw-Hill 1 2 3 N 4 N . Find the length of M in. A5 in. 1 2 1 B 3 2 2.5 cm © Glencoe/McGraw-Hill 1 ᎏᎏ ft or 6 in. 2 8. 2 ft 1 ᎏᎏ in. 2 5. 10 in. 0.05 mm 9. 3.5 mm 0.5 mm 6. 32 mm 7 5 8 cm in. 1 2 1ᎏᎏ inches long. 7 8 3 1 4 1ᎏᎏ in. 1.7 cm Glencoe Geometry 1 ᎏᎏ yd or 9 in. 4 10. 2ᎏᎏ yd 1 2 0.5 cm 7. 44 cm 1 T 苶S 苶 is between 1ᎏᎏ inches and or ᎏᎏ inch, so R 1 8 accurate to within one half of a quarter inch, 2ᎏᎏ in. 4. 1 4 2 is about 1ᎏᎏ inches. The measurement is 2. S Find the precision for each measurement. 3. cm 1. A 3 4 1 S Find the length of R S . The long marks are inches and the short marks are quarter inches. The length of 苶 RS 苶 R Example 2 Find the length of each line segment or object. Exercises The long marks are centimeters, and the shorter marks are millimeters. The length of M 苶N 苶 is 3.4 centimeters. The measurement is accurate to within 0.5 millimeter, so 苶 MN 苶 is between 3.35 centimeters and 3.45 centimeters long. cm M Example 1 A part of a line between two endpoints is called a line segment. The lengths of M 苶N 苶 and R 苶S 苶 are written as MN and RS. When you measure a segment, the precision of the measurement is half of the smallest unit on the ruler. Measure Line Segments 1-2 NAME ______________________________________________ DATE Linear Measure and Precision A x B 2x C C Q X R S 3 1–2 in. 2.0 cm Y 2.5 cm 3 – 4 Z in. T 1 4 4 ᎏᎏ in. 4.5 cm Y C 3 cm Glencoe Geometry 11 cm 11 cm Glencoe/McGraw-Hill Answers © B 5 cm A 9. A 苶B 苶 and C 苶D 苶 yes C 5 cm D 8 Y 3x ⫹ 5 9x 2 X 10. X 苶Y 苶 and Y 苶Z 苶 Z 5x ⫺ 1 no Glencoe Geometry Use the figures to determine whether each pair of segments is congruent. 8. RS ⫽ 4x, 苶 RS 苶⬵苶 ST 苶, and RT ⫽ 24. 3, 12 X 6 cm 2 3–4 in. B 1 4 3 ᎏᎏ in. 7. RS ⫽ 6x, ST ⫽12, and RT ⫽ 72. 10, 60 W A 6 in. 6. RS ⫽ 2x, ST ⫽ 5x ⫹ 4, and RT ⫽ 32. 4, 8 4. W 苶X 苶 2. B 苶C 苶 5. RS ⫽ 5x, ST ⫽ 3x, and RT ⫽ 48. 6, 30 Find x and RS if S is between R and T. 3. X 苶Z 苶 1. R 苶T 苶 Find the measurement of each segment. Assume that the art is not drawn to scale. Exercises Therefore, 苶 EF 苶 is 3.1 centimeters long. AB ⫹ BC ⫽ AC x ⫹ 2x ⫽ 2x ⫹ 5 3x ⫽ 2x ⫹ 5 x⫽5 AC ⫽ 2x ⫹ 5 ⫽ 2(5) ⫹ 5 ⫽ 15 F Find x and AC. ED ⫹ DF ⫽ EF 1.2 ⫹ 1.9 ⫽ EF 3.1 ⫽ EF D 2x ⫹ 5 Example 2 B M B is between A and C. E Find EF. 1.9 cm A P Calculate EF by adding ED and DF. 1.2 cm Example 1 Calculate Measures (continued) ____________ PERIOD _____ Study Guide and Intervention On PQ, to say that point M is between points P and Q means P, Q, and M are collinear and PM ⫹ MQ ⫽ PQ. On AC, AB ⫽ BC ⫽ 3 cm. We can say that the segments are congruent, or 苶 AB 苶⬵苶 BC 苶. Slashes on the figure indicate which segments are congruent. 1-2 NAME ______________________________________________ DATE Answers (Lesson 1-2) Lesson 1-2 © Linear Measure and Precision Skills Practice Glencoe/McGraw-Hill 1 2 about 55 mm cm 3 4 5 2. 0.5 cm A6 1 4 1in. P 11–4 in. N B 10.1 cm A 4.9 cm 7. A 苶C 苶 1 5.2 cm C © 5m D 3m Glencoe/McGraw-Hill yes E 3m B 2m C 13. 苶 BE 苶, 苶 CD 苶 12 yd no M 12 yd 14. M 苶P 苶, 苶 NP 苶 H 10; 60 12. XY ⫽ 2c ⫹ 1, YZ ⫽ 6c, and XZ ⫽ 81 8; 16 10. XY ⫽ 12, YZ ⫽ 2g, and XZ ⫽ 28 9 N 10 yd P no X 5 ft Y 9 ft 15. W 苶X 苶, 苶 WZ 苶 Glencoe Geometry W 5 ft Z Use the figures to determine whether each pair of segments is congruent. 6; 18 11. XY ⫽ 4m, YZ ⫽ 3m, and XZ ⫽ 42 5; 5 9. XY ⫽ 5p, YZ ⫽ p, and XY ⫽ 25 G 15 mm 9.7 mm 5.3 mm F 8. G 苶H 苶 1 ᎏᎏ in. 4 1 5. 9ᎏᎏ inches 2 2 ____________ PERIOD _____ Find the value of the variable and YZ if Y is between X and Z. 2ᎏᎏ in. Q 6. N 苶Q 苶 in. 1 about 2ᎏᎏ in. 4 4. 12 centimeters Find the measurement of each segment. 0.5 ft 3. 40 feet Find the precision for each measurement. 1. Find the length of each line segment or object. 1-2 NAME ______________________________________________ DATE (Average) 1 F 2 0.5 m 18.4 cm Q S 4.7 cm 5 8 23–8 in. 3ᎏᎏ in. A 7. A 苶D 苶 C D 2 5 X 89.6 cm 100 cm 10.4cm W 8. W 苶X 苶 0.5 mm 6; 8 3 ft W 3 ft yes D A 12. A 苶D 苶, 苶 BC 苶 12.9 in. 12.7 in. B C © Glencoe/McGraw-Hill C B F E , A B C D D E F A 10 5x F no G 13. G 苶F 苶, 苶 FE 苶 14. CARPENTRY Jorge used the figure at the right to make a pattern for a mosaic he plans to inlay on a tabletop. Name all of the congruent segments in the figure. no U 2 ft T 2 ft S 11. 苶 TU 苶, 苶 SW 苶 Y H D A C Glencoe Geometry E F E 6x B 10. JK ⫽ 2s, KL ⫽ s ⫹ 2, and JL ⫽ 5s ⫺ 10 Use the figures to determine whether each pair of segments is congruent. 3; 9 9. JK ⫽ 6r, KL ⫽ 3r, and JL ⫽ 27 4 5. 30.0 millimeters 3 ____________ PERIOD _____ Find the value of the variable and KL if K is between J and L. 23.1 cm P 苶S 苶 6. P Find the measurement of each segment. 1 ᎏᎏ in. 8 1 4 4. 7ᎏᎏ inches 3. 120 meters 42 mm cm 11–4 in. 2. Find the precision for each measurement. 11 16 in. 1ᎏᎏ in. 1. E 1 Linear Measure and Precision Practice Find the length of each line segment or object. 1-2 NAME ______________________________________________ DATE Answers (Lesson 1-2) Glencoe Geometry Lesson 1-2 © Glencoe/McGraw-Hill A7 4.5 cm A B C 4.5 cm Glencoe/McGraw-Hill century, centennial 11 Glencoe Geometry 6. A good way to remember terms used in mathematics is to relate them to everyday words you know. Give three words that are used outside of mathematics that can help you remember that there are 100 centimeters in a meter. Sample answer: cent, Helping You Remember 5. Suppose that S is a point on V 苶W 苶 and S is not the same point as V or W. Tell whether each of the following statements is always, sometimes, or never true. a. VS ⫽ SW sometimes b. S is between V and W. always c. VS ⫹ VW ⫽ SW never AB C D ; Sample answer: The two segments are congruent because they have the same measure or length. They are not equal because they are not the same segment. 4. Refer to the figure at the right. Which one of the following statements is true? Explain your answer. A CD 苶B 苶⫽苶 CD 苶 苶B A 苶⬵苶 苶 3. Find the precision of each measurement. a. 15 cm 0.5 cm b. 15.0 cm 0.05 cm 2. What is the smallest length marked on a 12-inch ruler? Sample answer: ᎏᎏ in. 16 What is the smallest length marked on a centimeter ruler? 1 mm 1 Sample answer: A line is infinite. Since it has no endpoints, a line does not have a definite length and cannot be measured. A line segment has two endpoints, so it has a definite length and can be measured. 1. Explain the difference between a line and a line segment and why one of these can be measured, while the other cannot. D The metric system is easier because you can change between the different units by just moving the decimal point. • Do you think it would be easier to learn the relationships between the different units of length in the customary system (used in the United States) or in the metric system? Explain your answer. Sample answer: • The basic unit of length in the metric system is the meter. How many meters are there in one kilometer? 1000 Read the introduction to Lesson 1-2 at the top of page 13 in your textbook. Why are units of measure important? Linear Measure and Precision Reading the Lesson © ____________ PERIOD _____ Reading to Learn Mathematics Pre-Activity 1-2 NAME ______________________________________________ DATE Enrichment A X Y D B X C D The locus is a set of 2 points, X and Y. A Y B Glencoe Geometry Answers Glencoe/McGraw-Hill 12 2. Conduct your own investigation of the locus of points equidistant from two segments. Describe your results on a separate sheet of paper. See students’ work. © P C D Q S The locus is a pair of line segments, S R and P Q . A R B Glencoe Geometry B and C D depends on the The locus of points x units from A B and C D are situated relative to one another. distance x and how A The locus is 1 segment X Y midway B and C D . between A C A 1. Suppose A, B, C, and D are four different points, and consider the locus 苶B 苶 and x units from 苶 CD 苶. Use any unit you find of all points x units from A convenient. The locus can take different forms. Sketch at least three possibilities. List some of the things that seem to affect the form of the locus. Sample answers are shown. from the segment AB is shown by two dashed segments with semicircles at both ends. a set of conditions. The locus of all points that are ᎏᎏ inch 1 4 A figure is a locus if it is the set of all points that satisfy B ____________ PERIOD _____ The distance from a point to a segment is zero if the point is on the segment. Otherwise, it is the length of the shortest segment from the point to the segment. Points Equidistant from Segments 1-2 NAME ______________________________________________ DATE Answers (Lesson 1-2) Lesson 1-2 © Distance and Midpoints Glencoe/McGraw-Hill b a 0 A8 1 2 B 3 Find AB. A(–2, –1) O x C (1, –1) B(1, 3) 苶 AB ⫽ 兹25 ⫽5 (AB)2 ⫽ (AC)2 ⫹ (BC)2 (AB)2 ⫽ (3)2 ⫹ (4)2 (AB)2 ⫽ 25 Pythagorean Theorem 4. EF 3 6. AG 17 8. DE 1 5. BG 15 7. BE 7 –10 –8 –6 B –4 C –2 0 DE 2 F 4 6 12. E(⫺12, 2), F(⫺9, 6) 5 10. R(⫺2, 3), S(3, 15) 13 © Glencoe/McGraw-Hill 15. C(11, ⫺12), D(6, 2) 221 14.9 13. A(0, 0), B(15, 20) 25 13 16. E(⫺2, 10), F(⫺4, 3) 8 G Glencoe Geometry 53 7.3 14. O(⫺12, 0), P(⫺8, 3) 5 Use the Distance Formula to find the distance between each pair of points. 11. M(1, ⫺2), N(9, 13) 17 9. A(0, 0), B(6, 8) 10 Use the Pythagorean Theorem to find the distance between each pair of points. 2. DG 9 1. BD 6 3. AF 12 A ⫽ 兹25 苶 ⫽5 AB ⫽ 兹苶 (3)2 ⫹苶 (4)2 AB ⫽ 兹苶 (1 ⫺ (苶 ⫺2))2 苶 ⫹ (3 ⫺苶 (⫺1))2苶 d ⫽ 兹苶 (x2 ⫺ 苶 x1)2 ⫹苶 (y2 ⫺苶 y1)2 Distance Formula Find the distance between A(⫺2, ⫺1) and B(1, 3). Example 2 (x2 ⫺ 苶 x1)2 ⫹苶 (y2 ⫺苶 y1)2 d ⫽ 兹苶 Distance Formula: a2 ⫹ b2 ⫽ c2 Pythagorean Theorem: Distance in the Coordinate Plane Use the number line to find each measure. Exercises AB ⫽ | (⫺4) ⫺ 2 | ⫽ |⫺ 6 | ⫽6 ⫺5 ⫺4 ⫺3 ⫺2 ⫺1 A Example 1 AB ⫽ | b ⫺ a | or | a ⫺ b | B A Distance on a Number Line y ____________ PERIOD _____ Study Guide and Intervention Distance Between Two Points 1-3 NAME ______________________________________________ DATE Distance and Midpoints 0 1 –1 –3 2 y ⫹y 2 冣 ⫺3 ⫹ 1 2 ⫺2 2 x ⫹x 2 y ⫹y 2 冣 冢 ⫺22⫹ 4 4⫹1 2 冣 1 2 8. D 苶E 苶 1 A –10 –8 –6 B C –4 –2 0 D 2 EF 4 6 © Glencoe/McGraw-Hill 13. S(10, ⫺22), T(9, 10) (9.5, ⫺6) 11. M(11, ⫺2), N(⫺9, 13) (1, 5.5) 9. A(0, 0), B(12, 8) (6, 4) 14 8 G Glencoe Geometry 14. M(⫺11, 2), N(⫺19, 6) (⫺15, 4) 12. E(⫺2, 6), F(⫺9, 3) (⫺5.5, 4.5) 10. R(⫺12, 8), S(6, 12) (⫺3, 10) Find the coordinates of the midpoint of a segment having the given endpoints. 7. B 苶D 苶 ⫺3ᎏᎏ 1 2 5. A 苶B 苶 ⫺8 6. B 苶G 苶 ᎏᎏ 4. E 苶G 苶 5 2. D 苶G 苶 4 3. A 苶F 苶 ⫺3 1. C 苶E 苶 ⫺1 Use the number line to find the coordinate of the midpoint of each segment. Exercises 1 2 1 2 ᎏ ᎏ M⫽ ᎏ ,ᎏ ⫽ ᎏᎏ, ᎏᎏ or (1, 2.5) 冢 Example 2 M is the midpoint of PQ for P(⫺2, 4) and Q(4, 1). Find the coordinates of M. 苶, then the coordinate of M is ᎏᎏ ⫽ ᎏᎏ or ⫺1. If M is the midpoint of 苶 PQ The coordinates of P and Q are ⫺3 and 1. –2 x ⫹x 2 1 2 1 2 ᎏ ᎏ ,ᎏ . then the coordinates of the midpoint of the segment are ᎏ 冢 If a segment has endpoints with coordinates (x1, y1) and (x2, y2), 2 a ⫹ᎏ b. then the coordinate of the midpoint of the segment is ᎏ If the coordinates of the endpoints of a segment are a and b, Find the coordinate of the midpoint of P Q . Q P Example 1 Midpoint on a Coordinate Plane Midpoint on a Number Line (continued) ____________ PERIOD _____ Study Guide and Intervention Midpoint of a Segment 1-3 NAME ______________________________________________ DATE Answers (Lesson 1-3) Glencoe Geometry Lesson 1-3 © Distance and Midpoints Skills Practice Glencoe/McGraw-Hill 4. MN 3 3. KN 11 –6 J –4 K –2 0 2 L 4 6 M 8 N 10 ____________ PERIOD _____ F O y G x 5 D O y x S 17 4.1 8. C(⫺3, ⫺1), Q(⫺2, 3) 6. 10 A9 –6 –4 –2 B 0 2 C 4 6 D 8 10 E 1 ᎏᎏ, 0 2 18. J(⫺4, 2), F(5, ⫺2) 12 © Glencoe/McGraw-Hill Q (8, 4) 19. N(2, 0), P(5, 2) Q (7, 2) 15 20. N(5, 4), P(6, 3) N (⫺5, 1) Glencoe Geometry 21. Q(3, 9), P(⫺1, 5) Find the coordinates of the missing endpoint given that P is the midpoint of N Q . (4, 2) 17. T(3, 1), U(5, 3) Find the coordinates of the midpoint of a segment having the given endpoints. 16. A 苶D 苶 1ᎏᎏ 15. 苶 BD 苶 3 1 2 14. B 苶C 苶 1 13. 苶 DE 苶 9 A 50 7.1 12. C(⫺3, 1), Q(2, 6) 7 10. W(⫺2, 2), R(5, 2) Use the number line to find the coordinate of the midpoint of each segment. 13 11. A(⫺7, ⫺3), B(5, 2) 6 9. Y(2, 0), P(2, 6) Use the Distance Formula to find the distance between each pair of points. 5 2.2 7. K(2, 3), F(4, 4) 5. Use the Pythagorean Theorem to find the distance between each pair of points. 2. JL 8 1. LN 6 Use the number line to find each measure. 1-3 NAME ______________________________________________ DATE (Average) Distance and Midpoints Practice 4. SV 8 2. TV 5 –10 –8 S –6 T –4 –2 U 0 V 2 4 W 6 8 ____________ PERIOD _____ O 65 8.1 M y Z x 6. 113 10.6 E O y x S 1 2 P –8 Q –6 –4 R –2 0 S 2 4 T (⫺10, ⫺5.5) 14. W(⫺12, ⫺7), T(⫺8, ⫺4) 6 D (⫺4, 3) 16. F(2, 9), E(⫺1, 6) F (5, 4) 17. D(⫺3, ⫺8), E(1, ⫺2) Glencoe Geometry Glencoe/McGraw-Hill Answers © 16 Glencoe Geometry 18. PERIMETER The coordinates of the vertices of a quadrilateral are R(⫺1, 3), S(3, 3), T(5, ⫺1), and U(⫺2, ⫺1). Find the perimeter of the quadrilateral. Round to the nearest tenth. 19.6 units D (3, ⫺2) 15. F(5, 8), E(4, 3) Find the coordinates of the missing endpoint given that E is the midpoint of D F . (⫺2, 5) 13. K(⫺9, 3), H(5, 7) Find the coordinates of the midpoint of a segment having the given endpoints. 12. P 苶R 苶 ⫺5 ᎏᎏ 11. 苶 ST 苶 2ᎏᎏ 1 2 10. Q 苶R 苶 ⫺4 9. R 苶T 苶 1 –10 18 4.2 8. U(1, 3), B(4, 6) Use the number line to find the coordinate of the midpoint of each segment. 15 7. L(⫺7, 0), Y(5, 9) Use the Distance Formula to find the distance between each pair of points. 5. Use the Pythagorean Theorem to find the distance between each pair of points. 3. ST 3 1. VW 4 Use the number line to find each measure. 1-3 NAME ______________________________________________ DATE Answers (Lesson 1-3) Lesson 1-3 © Glencoe/McGraw-Hill A10 ii. Distance Formula in the Coordinate Plane ⫹ i 冣 iii v. Midpoint of a Segment on a Number Line iv. Distance Formula on a Number Line 兹苶苶苶苶 ( ⫺2 ⫺ 4 )2 ⫹ ( 7 ⫺ ⫺3 )2 兹苶苶 ( ⫺6 )2 ⫹ ( 10 )2 36 ⫹ 100 兹苶苶 136 兹苶 MN ⫽ MN ⫽ MN ⫽ MN ⫽ 7 ). Glencoe/McGraw-Hill 17 Glencoe Geometry segment determined by the points is neither horizontal nor vertical, draw a right triangle that has the segment as its hypotenuse. The horizontal side will have length |x2 ⫺ x1| and the vertical side will have length |y2 ⫺ y1|. By the Pythagorean Theorem, d 2 ⫽ |x2 ⫺ x1| 2 ⫹ | y2 ⫺ y1| 2 ⫽ (x2 ⫺ x1) 2 ⫹ (y2 ⫺ y1) 2. 3. A good way to remember a new formula in mathematics is to relate it to one you already know. If you forget the Distance Formula, how can you use the Pythagorean Theorem to find the distance d between two points on a coordinate plane? Sample answer: If the Helping You Remember Find a decimal approximation for MN to the nearest hundredth. 11.66 兹苶苶苶苶 ( x2 ⫺ x1 )2 ⫹ ( y2 ⫺ y1 )2 d⫽ Let (x1, y1) ⫽ (4, ⫺3). Then (x2, y2) ⫽ ( ⫺2 , 2. Fill in the steps to calculate the distance between the points M(4, ⫺3) and N(⫺2, 7). 冢 e. ⫽ x1 ⫹ x2 y1 ⫹ y2 ᎏᎏ, ᎏᎏ 2 2 d. b2 c2 a2 c. XY ⫽ | a ⫺ b | iv iii. Midpoint of a Segment in the Coordinate Plane a⫹b b. ᎏᎏ 2 v i. Pythagorean Theorem a. d ⫽ 兹苶 (x2 ⫺ 苶 x1)2 ⫹苶 ( y2 ⫺苶 y1)2 ii 1. Match each formula or expression in the first column with one of the names in the second column. 5 F J 6. J 苶苶 K 5 5. 苶I苶 K 7.6 7. L 苶M 苶 4.1 3. 苶 RS 苶 4.2 E K D S 8. L 苶苶 N 7.2 4. Q 苶S 苶 5.8 N F B A Glencoe/McGraw-Hill 15. Use your answer from exercise 8 to calculate the length of segment LN in centimeters. Check by measuring with a centimeter ruler. 3.6 cm 13. Of all the segments shown on the grid, which is longest? What is its length? BC ⴝ 8.1 © M 18 Glencoe Geometry 16. Use a centimeter ruler to find the perimeter of triangle IJK to the nearest tenth of a centimeter. 7.8 cm Divide by 2 or multiply by 0.5. 14. On the grid, 1 unit ⫽ 0.5 cm. How can the answers above be used to find the measures in centimeters? 10. 䉭QRS 18 11. 䉭 DEF 16.6 12. 䉭 LMN 18.3 Answers shown are found by rounding segment lengths before adding. 9. 䉭 ABC 20.2 L Q R ____________ PERIOD _____ Use the grid above. Find the perimeter of each triangle to the nearest tenth of a unit. 2. M 苶苶 N 7 苶 3 1. 苶IJ Find each measure to the nearest tenth of a unit. EF ⫽ 兹苶 22 ⫹ 52苶 ⫽ 兹29 苶 ⬇ 5.4 units 2 E Example Find the measure of E F on the grid at the right. Locate a right triangle with EF as its longest side. I C You can easily find segment lengths on a grid if the endpoints are grid-line intersections. For horizontal or vertical segments, simply count squares. For diagonal segments, use the Pythagorean Theorem (proven in Chapter 7). This theorem states that in any right triangle, if the length of the longest side (the side opposite the right angle) is c and the two shorter sides have lengths a and b, then c2 ⫽ a2 ⫹ b2. • Find AB in this figure. Write your answer both as a radical and as a decimal number rounded to the nearest tenth. 61 units; 7.8 units Evenly-spaced horizontal and vertical lines form a grid. • Look at the triangle in the introduction to this lesson. What is the special 苶B 苶 in this triangle? hypotenuse name for A Enrichment Lengths on a Grid 1-3 NAME ______________________________________________ DATE Read the introduction to Lesson 1-3 at the top of page 21 in your textbook. Lesson 1-3 How can you find the distance between two points without a ruler? Distance and Midpoints Reading the Lesson © ____________ PERIOD _____ Reading to Learn Mathematics Pre-Activity 1-3 NAME ______________________________________________ DATE Answers (Lesson 1-3) Glencoe Geometry © Angle Measure Glencoe/McGraw-Hill S P 1 2 R 3 Q T A11 B © Glencoe/McGraw-Hill 6. ⬔NPS 45; acute 5. ⬔RPN 90; right 19 C B E C D 1 M 2 A B R S 3 C Glencoe Geometry P N 4 c. ⬔EBC Using a protractor, m⬔EBC ⫽ 90. ⬔EBC is a right angle. b. ⬔DBC Using a protractor, m⬔DBC ⫽ 115. 180 ⬎ 115 ⬎ 90, so ⬔DBC is an obtuse angle. a. ⬔ABD Using a protractor, m⬔ABD ⫽ 50. 50 ⬍ 90, so ⬔ABD is an acute angle. A D Measure each angle in the figure and classify it as right, acute, or obtuse. 4. ⬔MPR 120; obtuse A Measure each angle and classify it as right, acute, or obtuse. Example 2 3. Write another name for ⬔DBC. ⬔3 or ⬔CBD , DC 2. Name the sides of ⬔BDC. DB 1. Name the vertex of ⬔4. Refer to the figure. Exercises b. Name the sides of ⬔1. , RP RS a. Name all angles that have R as a vertex. Three angles are ⬔1, ⬔2, and ⬔3. For other angles, use three letters to name them: ⬔SRQ, ⬔PRT, and ⬔SRT. Example 1 A right angle is an angle whose measure is 90. An acute angle has measure less than 90. An obtuse angle has measure greater than 90 but less than 180. 1 B ____________ PERIOD _____ Study Guide and Intervention Measure Angles If two noncollinear rays have a common endpoint, they form an angle. The rays are the sides of the angle. The common endpoint is the vertex. The angle at the right can be named as ⬔A, ⬔BAC, ⬔CAB, or ⬔1. 1-4 NAME ______________________________________________ DATE m⬔NPR ⫽ (2x ⫹ 14) ⫹ (x ⫹ 34) ⫽ 54 ⫹ 54 ⫽ 108 Glencoe Geometry Glencoe/McGraw-Hill Answers © A P D S M 1 T B 4 E 2 3 Q P N C F R R 20 Glencoe Geometry and BF are bisectors, m⬔2 ⫹ m⬔3 must equal half the Yes; since BD total angle measure, and half of 180 is 90. 6. Is ⬔DBF a right angle? Explain. 100 5. If m⬔2 ⫽ 6y ⫹ 2 and m⬔1 ⫽ 8y ⫺ 14, find m⬔ABE. 50 4. If m⬔1 ⫽ 4x ⫹ 10 and m⬔2 ⫽ 5x, find m⬔2. 80 3. If m⬔EBF ⫽ 6x ⫹ 4 and m⬔CBF ⫽ 7x ⫺ 2, find m⬔EBC. and BC are opposite rays, BF bisects ⬔CBE, and BA bisects ⬔ABE. BD 56 2. If m⬔PQS ⫽ 3x ⫹ 13 and m⬔SQT ⫽ 6x ⫺ 2, find m⬔PQT. 4 1. If m⬔PQT ⫽ 60 and m⬔PQS ⫽ 4x ⫹ 14, find the value of x. bisects ⬔PQT, and QP and QR are opposite rays. QS Exercises 2x ⫹ 14 ⫽ x ⫹ 34 2x ⫹ 14 ⫺ x ⫽ x ⫹ 34 ⫺ x x ⫹ 14 ⫽ 34 x ⫹ 14 ⫺ 14 ⫽ 34 ⫺ 14 x ⫽ 20 Example Refer to the figure above. If m⬔MPN ⫽ 2x ⫹ 14 and m⬔NPR ⫽ x ⫹ 34, find x and find m⬔MPR. Since PN bisects ⬔MPR, ⬔MPN ⬵ ⬔NPR, or m⬔MPN ⫽ m⬔NPR. Angles that have the same measure are congruent angles. A ray that divides an angle into two congruent angles is called an angle bisector. In the figure, PN is the angle bisector of ⬔MPR. Point N lies in the interior of ⬔MPR and ⬔MPN ⬵ ⬔NPR. Angle Measure (continued) ____________ PERIOD _____ Study Guide and Intervention Congruent Angles 1-4 NAME ______________________________________________ DATE Answers (Lesson 1-4) Lesson 1-4 © Angle Measure Skills Practice Glencoe/McGraw-Hill V 3. ⬔2 A12 T W 100⬚, obtuse 16. ⬔QMO 40⬚, acute 14. ⬔OMN © Glencoe/McGraw-Hill 55 21 18. If m⬔ABF ⫽ 7x ⫺ 8 and m⬔EBF ⫽ 5x ⫹ 10, find m⬔EBF. 40 17. If m⬔EBD ⫽ 4x ⫹ 16 and m⬔DBC ⫽ 6x ⫹ 4, find m⬔EBD. bisects ⬔EBC, and BF bisects ⬔ABE. BD are opposite rays, and BC ALGEBRA In the figure, BA 140⬚, obtuse 15. ⬔QMN 90⬚, right 13. ⬔NMP S W 1 5 U T 2V 3 4 L Q A F B E C D N Glencoe Geometry M P O ____________ PERIOD _____ ⬔WVT, ⬔TVW, ⬔WVU, ⬔UVW 12. ⬔2 ⬔UTS, ⬔STU 10. ⬔4 , WV WT 8. ⬔1 , TW TS 6. ⬔5 4. ⬔5 2. ⬔1 Measure each angle and classify it as right, acute, or obtuse. ⬔STW, ⬔5 11. ⬔WTS ⬔WTV, ⬔VTW 9. ⬔3 Write another name for each angle. , TV TS 7. ⬔STV , TS TU 5. ⬔4 Name the sides of each angle. T 1. ⬔4 Name the vertex of each angle. For Exercises 1–12, use the figure at the right. 1-4 NAME ______________________________________________ DATE (Average) Angle Measure Practice O M P 20⬚, acute 14. ⬔UZT 70⬚, acute 12. ⬔YZW © Glencoe/McGraw-Hill 22 m⬔1 ⫽ 90, right angle; m⬔2 ⫽ 130, obtuse 17. TRAFFIC SIGNS The diagram shows a sign used to warn drivers of a school zone or crossing. Measure and classify each numbered angle. 16. If m⬔FCG ⫽ 9x ⫹ 3 and m⬔GCB ⫽ 13x ⫺ 9, find m⬔GCB. 30 15. If m⬔DCE ⫽ 4x ⫹ 15 and m⬔ECF ⫽ 6x ⫺ 5, find m⬔DCE. 55 bisects ⬔DCF, and CG bisects ⬔FCB. CE M 5 4 6 R T U F E G V Y Glencoe Geometry 1 2 B C D Z W X 7 O 8 1 P Q 2 3 N ____________ PERIOD _____ ⬔MPO, ⬔OPM, ⬔MPN, ⬔NPM 10. ⬔1 , MN MO 8. ⬔OMN are opposite rays, and CD ALGEBRA In the figure, CB 110⬚, obtuse 13. ⬔TZW 90⬚, right 11. ⬔UZW M , PM PR 6. ⬔2 4. ⬔NMP 2. ⬔3 Measure each angle and classify it as right, acute, or obtuse. ⬔3, ⬔RPQ 9. ⬔QPR Write another name for each angle. , OP or OR OM 7. ⬔MOP , NO or NP or NR NM 5. ⬔6 Name the sides of each angle. 3. ⬔8 1. ⬔5 Name the vertex of each angle. For Exercises 1–10, use the figure at the right. 1-4 NAME ______________________________________________ DATE Answers (Lesson 1-4) Glencoe Geometry Lesson 1-4 © Glencoe/McGraw-Hill A13 Glencoe/McGraw-Hill 23 Glencoe Geometry Sample answer: Congruent segments and congruent angles are alike because they both involve a pair of figures with the same measure. They are different because congruent segments have the same length, which can be measured in units such as inches or centimeters, while congruent angles have the same degree measure. 3. A good way to remember related geometric ideas is to compare them and see how they are alike and how they are different. Give some similarities and differences between congruent segments and congruent angles. Helping You Remember 1. Match each description in the first column with one of the terms in the second column. Some terms in the second column may be used more than once or not at all. a. a figure made up of two noncollinear rays with a 1. vertex common endpoint 4 2. angle bisector b. angles whose degree measures are less than 90 8 3. opposite rays c. angles that have the same measure 6 4. angle d. angles whose degree measures are between 90 and 180 5 5. obtuse angles e. a tool used to measure angles 10 6. congruent angles f. the common endpoint of the rays that form an angle 1 7. right angles g. a ray that divides an angle into two congruent angles 2 8. acute angles 9. compass 10. protractor 2. Use the figure to name each of the following. E a. a right angle ⬔ABE or ⬔EBG F D b. an obtuse angle ⬔ABF or ⬔ABC 28⬚ 28⬚ C c. an acute angle ⬔EBF, ⬔FBC, ⬔CBG, ⬔EBC, or ⬔FBG d. a point in the interior of ⬔EBC F A B G e. a point in the exterior of ⬔EBA F, C, or G f. the angle bisector of ⬔EBC BF g. a point on ⬔CBE C, B, or E and BF h. the sides of ⬔ABF BA and BG i. a pair of opposite rays BA j. the common vertex of all angles shown in the figure B k. a pair of congruent angles ⬔EBF and ⬔FBC, or ⬔ABE and ⬔EBG l. the angle with the greatest measure ⬔ABG 55⬚30⬘15⬙ 5. 34⬚29⬘45⬙ 62⬚44⬘ 2. 27⬚16⬘ 2⬚57⬘57⬙ 6. 87⬚2⬘3⬙ 74⬚06⬘ 3. 15⬚54⬘ Glencoe Geometry Glencoe/McGraw-Hill Answers © 81⬚7⬘1⬙ 13. 98⬚52⬘59⬙ 24 170⬚57⬘28⬙ 14. 9⬚2⬘32⬙ 140⬚38⬘6⬙ 11. 39⬚21⬘54⬙ 10. 45⬚16⬘24⬙ 134⬚43⬘36⬙ 95⬚48⬘ 8. 84⬚12⬘ 59⬚42⬘ 7. 120⬚18⬘ Glencoe Geometry 178⬚57⬘57⬙ 15. 1⬚2⬘3⬙ 50⬚41⬘24⬙ 12. 129⬚18⬘36⬙ 69⬚58⬘ 9. 110⬚2⬘ Two angles are supplementary if the sum of their measures is 180⬚. Find the supplement of each of the following angles. 60⬚41⬘38⬙ 4. 29⬚18⬘22⬙ 54⬚45⬘ 1. 35⬚15⬘ Two angles are complementary if the sum of their measures is 90⬚. Find the complement of each of the following angles. 90⬚ ⫽ 89°60⬘ 70.4⬚ ⫽ 70°24⬘ 67ᎏᎏ⬚ ⫽ 67⬚30⬘ 1 2 60⬙ ⫽ 1⬘ 60⬘ ⫽ 1⬚ Angles are measured in degrees (⬚). Each degree of an angle is divided into 60 minutes (⬘), and each minute of an angle is divided into 60 seconds (⬙). Enrichment ____________ PERIOD _____ Angle Relationships 1-4 NAME ______________________________________________ DATE Read the introduction to Lesson 1-4 at the top of page 29 in your textbook. • A semicircle is half a circle. How many degrees are there in a semicircle? 180 • How many degrees are there in a quarter circle? 90 Lesson 1-4 How big is a degree? Angle Measure Reading the Lesson © ____________ PERIOD _____ Reading to Learn Mathematics Pre-Activity 1-4 NAME ______________________________________________ DATE Answers (Lesson 1-4) © ____________ PERIOD _____ Angle Relationships Study Guide and Intervention Glencoe/McGraw-Hill A14 T U 5 B 6 C Exercises ⬔6 and ⬔5 are adjacent angles whose noncommon sides are opposite rays. The angles form a linear pair. A D ⬔SRT and ⬔TRU have a common vertex and a common side, but no common interior points. They are adjacent angles. R S d. b. 4 3N 1 2 S A 60⬚ B adjacent vertical © G 60⬚ V P 1 U 2 T V R 6Q 3 4 5 T N U S R S Glencoe/McGraw-Hill 36 and 54 25 Glencoe Geometry 8. Find the measures of two complementary angles if the difference in their measures is 18. and ⬔VNT or ⬔VNT and ⬔TNU 7. Identify an angle supplementary to ⬔TNU. ⬔UNS or ⬔TNR 6. Identify two acute adjacent angles. ⬔RNV 5. Identify two obtuse vertical angles. ⬔RNT and ⬔SNU For Exercises 5–7, refer to the figure at the right. 4. ⬔3 and ⬔2 F 120⬚ ⬔A and ⬔B are two angles whose measures have a sum of 90. They are complementary. ⬔F and ⬔G are two angles whose measures have a sum of 180. They are supplementary. 30⬚ linear pair; adjacent 2. ⬔1 and ⬔6 3. ⬔1 and ⬔5 adjacent 1. ⬔1 and ⬔2 P ⬔1 and ⬔3 are nonadjacent angles formed by two intersecting lines. They are vertical angles. ⬔2 and ⬔4 are also vertical angles. M R Identify each pair of angles as adjacent, vertical, and/or as a linear pair. c. a. Example Identify each pair of angles as adjacent angles, vertical angles, and/or as a linear pair. Adjacent angles are angles in the same plane that have a common vertex and a common side, but no common interior points. Vertical angles are two nonadjacent angles formed by two intersecting lines. A pair of adjacent angles whose noncommon sides are opposite rays is called a linear pair. Pairs of Angles 1-5 NAME ______________________________________________ DATE © ⫽ ⫽ ⫽ ⫽ ⫽ m⬔DZP 90 90 84 7 x ⫽ 15, y ⫽ 8 Divide each side by 12. Subtract 6 from each side. Simplify. Substitution Sum of parts ⫽ whole Glencoe/McGraw-Hill 26 y ⫽ 15, m⬔RPT ⫽ 55, m⬔TPW ⫽ 35 6. Find y, m⬔RPT, and m⬔TPW. x ⫽ 8, m⬔PQS ⫽ 24, m⬔SQR ⫽ 66 5. Find x, m⬔PQS, and m⬔SQR. 4. If m⬔EBF ⫽ 7y ⫺ 3 and m⬔FBC ⫽ 3y ⫹ 3, find y so ⊥ that EB BC . 9 ⊥ BF . Find x. 3. m⬔EBF ⫽ 3x ⫹ 10, m⬔DBE ⫽ x, and BD 2. Find m⬔MSN. 90 ⊥ MQ . 1. Find x and y so that NR Exercises m⬔DZQ ⫹ m⬔QZP (9x ⫹ 5) ⫹ (3x ⫹ 1) 12x ⫹ 6 12x x Example Find x so that D Z ⊥P Z . If 苶 DZ 苶⊥苶 PZ 苶, then m⬔DZP ⫽ 90. x ⫽ 20 W D A N 5x ⬚ T S V Q Glencoe Geometry P R R F C B P C P x⬚ (8x ⫹ 2)⬚ 3x ⬚ S E B (4y ⫺ 5)⬚ Q P D R (9y ⫹ 18)⬚ S Z A Q (9x ⫹ 5)⬚ (3x ⫹ 1)⬚ (2y ⫹ 5)⬚ M D Lines, rays, and segments that form four right angles are perpendicular. The right angle symbol indicates that the lines is perpendicular to are perpendicular. In the figure at the right, AC BD , ⊥ or AC BD . Angle Relationships (continued) ____________ PERIOD _____ Study Guide and Intervention Perpendicular Lines 1-5 NAME ______________________________________________ DATE Answers (Lesson 1-5) Glencoe Geometry Lesson 1-5 A15 Angle Relationships Skills Practice Glencoe/McGraw-Hill 27 No; the angles do not share a common side. 13. ⬔VZU is adjacent to ⬔YZX. Yes; the sum of their measures is 180 since the angles form a linear pair. 12. ⬔YZU and ⬔UZV are supplementary. Yes; it is marked with a right angle symbol. 11. ⬔WZU is a right angle. Determine whether each statement can be assumed from the figure. Explain. 10. If m⬔PTQ ⫽ 3y ⫺ 10 and m⬔QTR ⫽ y, find y so that ⬔PTR is a right angle. 25 . 9 9. If m⬔RTS ⫽ 8x ⫹ 18, find x so that TR ⊥ TS X Y P Q W V U S Glencoe Geometry Z T R 8. The measure of the supplement of an angle is 36 less than the measure of the angle. Find the measures of the angles. 72, 108 7. Find the measures of an angle and its complement if one angle measures 18 degrees more than the other. 36, 54 6. Name an angle supplementary to ⬔FKG. ⬔EKF or ⬔GKH 5. Name an angle complementary to ⬔EKH. ⬔GKJ ALGEBRA For Exercises 9–10, use the figure at the right. © 2. Name a linear pair whose vertex is B. ⬔GBC, ⬔CBA Sample answer: ⬔GFH, ⬔CFE 1. Name two obtuse vertical angles. For Exercises 1–4, use the figure at the right and a protractor. A B D C G E H F Glencoe Geometry Answers Glencoe/McGraw-Hill 28 Sample answer: Beacon ⊥ Main; Olive divides two of the angles formed by Bacon and Main into pairs of complementary angles. 12. STREET MAPS Darren sketched a map of the cross streets nearest to his home for his friend Miguel. Describe two different angle relationships between the streets. No; the angles are adjacent. 11. ⬔MQN and ⬔MQR are vertical angles. angles whose noncommon sides are opposite rays. 10. ⬔SRQ and ⬔QRP is a linear pair. Yes; they are adjacent No; m⬔NQP is not known to be 90. 9. ⬔NQO and ⬔OQP are complementary. Determine whether each statement can be assumed from the figure. Explain. 8. If m⬔BGC ⫽ 16x ⫺ 4 and m⬔CGD ⫽ 2x ⫹ 13, find x so that ⬔BGD is a right angle. 4.5 7. If m⬔FGE ⫽ 5x ⫹ 10, find x so that FC ⊥ AE . 16 M E G A R Q O D C Olive Ma in P Glencoe Geometry S N B 6. If a supplement of an angle has a measure 78 less than the measure of the angle, what are the measures of the angles? 129, 51 ALGEBRA For Exercises 7–8, use the figure at the right. © F 5. Two angles are complementary. The measure of one angle is 21 more than twice the measure of the other angle. Find the measures of the angles. 23, 67 4. Name an angle adjacent and supplementary to ⬔DCB. ⬔BCG or ⬔DCH J G (Average) Angle Relationships Practice ____________ PERIOD _____ 4. Name two acute adjacent angles. ⬔FKG, ⬔GKJ K F 1-5 NAME ______________________________________________ DATE 3. Name an angle not adjacent to but complementary to ⬔FGC. ⬔FED H E ____________ PERIOD _____ Lesson 1-5 3. Name a linear pair. Sample answer: ⬔EKH, ⬔EKF 2. Name two obtuse vertical angles. ⬔EKF, ⬔HKG 1. Name two acute vertical angles. ⬔EKH, ⬔FKG For Exercises 1–6, use the figure at the right and a protractor. 1-5 NAME ______________________________________________ DATE n Glencoe/McGraw-Hill aco © Be Answers (Lesson 1-5) © Glencoe/McGraw-Hill A16 2n Glencoe/McGraw-Hill 29 Glencoe Geometry answer: Supplementary means something added to complete a thing. An angle and its supplement can be joined to obtain a linear pair. 4. Look up the nonmathematical meaning of supplementary in your dictionary. How can this definition help you to remember the meaning of supplementary angles? Sample Helping You Remember b. If two angles are complementary and x is the measure of one of the angles, then the 90 ⫺ x measure of the other angle is . a. If two angles are supplementary and x is the measure of one of the angles, then the 180 ⫺ x measure of the other angle is . 3. Complete each sentence. i. If two angles form a linear pair, one is acute and the other is obtuse. sometimes h. The two angles in a linear pair are both acute. never g. Vertical angles are complementary. sometimes f. Vertical angles are supplementary. sometimes e. When two perpendicular lines intersect, four congruent angles are formed. always d. If two angles are complementary, they are adjacent. sometimes c. If two angles are supplementary, they are congruent. sometimes b. If two angles form a linear pair, they are complementary. never a. If two angles are adjacent angles, they form a linear pair. sometimes 2. Tell whether each statement is always, sometimes, or never true. ⬔4 and ⬔1 g. four pairs of supplementary angles ⬔1 and ⬔2, ⬔2 and ⬔3, ⬔3 and ⬔4, f. four linear pairs ⬔1 and ⬔2, ⬔2 and ⬔3, ⬔3 and ⬔4, ⬔4 and ⬔1 e. two pairs of vertical angles ⬔1 and ⬔3, ⬔2 and ⬔4 d. four pairs of adjacent angles ⬔1 and ⬔2, ⬔2 and ⬔3, ⬔3 and ⬔4, ⬔4 and ⬔1 c. a pair of obtuse vertical angles ⬔1 and ⬔3 b. a pair of acute vertical angles ⬔2 and ⬔4 a. two pairs of congruent angles ⬔1 and ⬔3, ⬔2 and ⬔4 1. Name each of the following in the figure at the right. 65⬚ 2 3 4 1 • How many separate angles are formed if n lines intersect at a common point? (Do not count an angle whose interior includes part of another angle.) • How many separate angles are formed if three lines intersect at a common point? (Do not use an angle whose interior includes part of another angle.) 6 7 1 5 2 3 3 1 4 5 6 7 8 © 1 7 2 5 3 3 4 5 6 7 8 9 17 19 18 15 16 13 14 11 12 11 12 13 14 15 16 17 18 19 Glencoe/McGraw-Hill See students’ work. 30 3. Create your own design. You may use several angles, and the angles may overlap. 9 8 6 4 2 1 2. Complete the following design. 1. Complete the section of the star design above by connecting pairs of points that have the same number. To make a complete star, make the same design in six 60° angles that have a common central vertex. 8 6 4 2 To begin the star design, draw a 60° angle. Mark eight equally-spaced points on each ray, and number the points as shown below. Then connect pairs of points that have the same number. The star design at the right was created by a method known as curve stitching. Although the design appears to contain curves, it is made up entirely of line segments. Enrichment Curve Stitching 1-5 NAME ______________________________________________ DATE Read the introduction to Lesson 1-5 at the top of page 37 in your textbook. Lesson 1-5 What kinds of angles are formed when streets intersect? Angle Relationships Reading the Lesson © ____________ PERIOD _____ Reading to Learn Mathematics Pre-Activity 1-5 NAME ______________________________________________ DATE Glencoe Geometry ____________ PERIOD _____ Answers (Lesson 1-5) Glencoe Geometry © Polygons Study Guide and Intervention ____________ PERIOD _____ Glencoe/McGraw-Hill A17 F Exercises The polygon has 5 sides, so it is a pentagon. It is convex. All sides are congruent and all angles are congruent, so it is a regular pentagon. d. b. J K L The figure has 8 congruent sides and 8 congruent angles. It is convex and is a regular octagon. The figure is not closed, so it is not a polygon. I H © triangle; convex; irregular hexagon; convex; regular Glencoe/McGraw-Hill 4. 1. 5. 2. 31 pentagon; concave; irregular quadrilateral; convex; irregular 6. 3. Glencoe Geometry octagon; concave; irregular pentagon; concave; irregular Name each polygon by its number of sides. Then classify it as concave or convex and regular or irregular. c. G E The polygon has 4 sides, so it is a quadrilateral. It is concave because part of D 苶E 苶 or 苶 EF 苶 lies in the interior of the figure. Because it is concave, it cannot have all its angles congruent and so it is irregular. a. D Example Name each polygon by its number of sides. Then classify it as concave or convex and regular or irregular. Polygons A polygon is a closed figure formed by a finite number of coplanar line segments. The sides that have a common endpoint must be noncollinear and each side intersects exactly two other sides at their endpoints. A polygon is named according to its number of sides. A regular polygon has congruent sides and congruent angles. A polygon can be concave or convex. 1-6 NAME ______________________________________________ DATE c 5 in. Exercises P⫽a⫹b⫹c ⫽3⫹4⫹5 ⫽ 12 in. 3 in. a 4 in. b b. 96 yd 12 yd 19 yd 9 cm 2.5 cm 24 yd 27 yd 3.5 cm 14 yd 3 cm 4. 2. square 10 cm 1 cm 22 ft 5.5 ft s 5 cm c. Glencoe Geometry Glencoe/McGraw-Hill Answers © rectangle 16, 32 x 2x 5. P ⫽ 96 32 x 2x 8, 10, 10, 20 x⫺2 6. P ⫽ 48 ᐉ 3 ft ᐉ x w Glencoe Geometry P ⫽ 2ᐉ ⫹ 2w ⫽ 2(3) ⫹ 2(2) ⫽ 10 ft 2 ft w Find the length of each side of the polygon for the given perimeter. 3. 1. s 5 cm 5 cm s P ⫽ 4s ⫽ 4(5) ⫽ 20 cm 5 cm s Find the perimeter of each figure. a. Example Write an expression or formula for the perimeter of each polygon. Find the perimeter. The perimeter of a polygon is the sum of the lengths of all the sides of the polygon. There are special formulas for the perimeter of a square or a rectangle. Polygons (continued) ____________ PERIOD _____ Study Guide and Intervention Perimeter 1-6 NAME ______________________________________________ DATE Answers (Lesson 1-6) Lesson 1-6 © Polygons Skills Practice ____________ PERIOD _____ Glencoe/McGraw-Hill heptagon; convex; regular quadrilateral; convex; irregular 5. 2. A18 40 yd 20 yd 98 yd 18 yd 20 yd 8. 20 m 2m 4m 5m 3m 9. 6. 3. 32 in. 2 in. 2 in. 2 in. 2 in. 2 in. 2 in. © Glencoe/McGraw-Hill All are 13 mm. 13. P ⫽ 104 millimeters 33 All are 28 km. 14. P ⫽ 84 kilometers w Glencoe Geometry 9 ft, 9 ft, 35 ft, 35 ft 4w ⫺ 1 15. P ⫽ 88 feet ALGEBRA Find the length of each side of the polygon for the given perimeter. 14.3 units 12. quadrilateral LMNO with vertices L(⫺1, 4), M(3, 4), N(2, 1), and O(⫺2, 1) 20 units 11. quadrilateral QRST with vertices Q(⫺3, 2), R(1, 2), S(1, ⫺4), and T(⫺3, ⫺4) 12 units 10. triangle ABC with vertices A(3, 5), B(3, 1), and C(0, 1) 10 in. 10 in. dodecagon; concave; irregular pentagon; concave; irregular COORDINATE GEOMETRY Find the perimeter of each polygon. 7. 6m quadrilateral; convex; irregular triangle; convex; regular Find the perimeter of each figure. 4. 1. Name each polygon by its number of sides and then classify it as convex or concave and regular or irregular. 1-6 NAME ______________________________________________ DATE Polygons Practice (Average) ____________ PERIOD _____ hexagon; concave; irregular 2. 53 mm 10 mm 7 mm 18 mm 18 mm 5. 86 mi 21 mi 32 mi 6. 3. 4 cm n 2x ⫺ 3 17 cm, 17 cm, 5 cm 3x ⫹ 5 10. P ⫽ 39 centimeters 4 in. 16 in. 16 in. © Glencoe/McGraw-Hill 48 in. 34 4 in. Glencoe Geometry 13. If Jasmine doubles the width of the scarf, how many inches of fringe will she need? 40 in. 12. How many inches of fringe does she need to purchase? 5x ⫺ 4 2x ⫹ 2 18 ft, 18 ft, 36 ft, 17 ft x⫹9 11. P ⫽ 89 feet SEWING For Exercises 12–13, use the following information. Jasmine plans to sew fringe around the scarf shown in the diagram. 3 in., 3 in., 10 in., 10 in. 6n ⫺ 8 9. P ⫽ 26 inches ALGEBRA Find the length of each side of the polygon for the given perimeter. 17.5 units 8. pentagon STUVW with vertices S(0, 0), T(3, ⫺2), U(2, ⫺5), V(⫺2, ⫺5), and W(⫺3, ⫺2) 25.1 units 7. quadrilateral OPQR with vertices O(⫺3, 2), P(1, 5), Q(6, 4), and R(5, ⫺2) 14 cm 4 cm 6 cm 6 cm 14 cm 6 cm 56 cm 2 cm quadrilateral; convex; irregular COORDINATE GEOMETRY Find the perimeter of each polygon. 4. 33 mi nonagon; convex; regular Find the perimeter of each figure. 1. Name each polygon by its number of sides and then classify it as convex or concave and regular or irregular. 1-6 NAME ______________________________________________ DATE Answers (Lesson 1-6) Glencoe Geometry Lesson 1-6 © Glencoe/McGraw-Hill A19 Sides intersect at a point that is not an endpoint. pentagon, convex, regular b. quadrilateral, concave, not regular c. quadrilateral, convex, not regular iv. P ⫽ 12s v. P ⫽ 2ᐉ ⫹ 2w vi. P ⫽ 4s f. triangle iii iii. P ⫽ a ⫹ b ⫹ c c. regular hexagon ii d. rectangle v ii. P ⫽ 6s b. square vi e. regular octagon i i. P ⫽ 8s a. regular dodecagon iv 4. Match each polygon in the first column with the formula in the second column that can be used to find its perimeter. (s represents the length of each side of a regular polygon.) 3. What is another name for a regular quadrilateral? a square a. Glencoe/McGraw-Hill 35 Glencoe Geometry Sample answer: A regular polygon looks the same no matter what part you look at. The sides are the same length, and the angles are the same size. 5. One way to remember the meaning of a term is to explain it to another person. How would you explain to a friend what a regular polygon is? Helping You Remember © curved (not all made up of segments) 2. Name each polygon by its number of sides. Then classify it as convex or concave and regular or not regular. not closed b. 1. Tell why each figure is not a polygon. c. Sample answer: square, rectangle, parallelogram, trapezoid Name four different shapes that can each be formed by four sticks connected to form a closed figure. Assume you have sticks with a good variety of lengths. Read the introduction to Lesson 1-6 at the top of page 45 in your textbook. How are polygons related to toys? Polygons Reading the Lesson a. ____________ PERIOD _____ Reading to Learn Mathematics Pre-Activity 1-6 NAME ______________________________________________ DATE Enrichment ____________ PERIOD _____ A2 ⫽ 3 ⭈ 3 ⫽9 m2. 2m 2m 1 4 cm 4 in. 2 cm 2 in. 4 cm 8 cm 4 cm 2 cm 4 cm 6 cm 4 in. 1 in. A ⫽ 40 cm2 P ⫽ 44 cm A ⫽ 12 in2 P ⫽ 20 in. 4. 2. 3 ft 7m 7 ft 9 ft 2 ft 13 m 26 m 6m 4 ft 5m 12 m A ⫽ 320 m2 P ⫽ 96 m Glencoe Geometry Glencoe/McGraw-Hill See students’ work. Answers © 6. 96 m 7. 44 cm 36 9. Describe the steps you used to find the perimeter in Exercise 1. 5. 17 in. 8. 48 ft Glencoe Geometry A ⫽ 90 ft2 P ⫽ 46 ft 9m 3m 2 3m 5m For Exercises 5–8, find the perimeter of the figures in Exercises 1–4. 3. 1. 6 ft 9m 9m Find the area and perimeter of each irregular shape. The area of the irregular shape is 27 18 ⫹ 9 ⫽ 27 A ⫽ ᐉw A1 ⫽ 9 ⭈ 2 ⫽ 18 Example Find the area of the figure at the right. Separate the figure into two rectangles. However, many figures are combinations of two or more rectangles creating irregular shapes. To find the area of an irregular shape, it helps to separate the shape into rectangles, calculate the formula for each rectangle, then find the sum of the areas. Perimeter: P ⫽ 2ᐉ ⫹ 2w Area: A ⫽ ᐉw, where ᐉ is the length and w is the width Two formulas that are used frequently in mathematics are perimeter and area of a rectangle. Perimeter and Area of Irregular Shapes 1-6 NAME ______________________________________________ DATE Answers (Lesson 1-6) Lesson 1-6 Chapter 1 Assessment Answer Key Form 1 Page 37 1. 2. D B 4. C 11. B 12. A 13. D 14. D 15. B 16. C 17. A A 7. A 8. C 18. D 19. D A 20. 10. 1. B 2. D 3. C 4. A 5. B 6. C 7. C 8. C 9. A 10. B D 6. 9. Page 38 A 3. 5. Form 2A Page 39 B B B: 12 yd (continued on the next page) © Glencoe/McGraw-Hill A20 Glencoe Geometry Chapter 1 Assessment Answer Key 11. C 12. A Form 2B Page 41 1. 2. 13. 14. C 15. B 16. D 17. B 4. B 20. A 32 © Glencoe/McGraw-Hill 11. A 12. B 13. D 14. C 15. D 16. A 17. B 18. C D D A 5. C 6. B A 19. B: B C 3. 18. Page 42 Answers Form 2A (continued) Page 40 7. A 8. D 19. C 9. C 20. C 10. B B: A21 64 Glencoe Geometry Chapter 1 Assessment Answer Key Form 2C Page 43 Page 44 Sample answer: DE 1. 2. A, B, C 3. AB 15. 64°, acute 16. 6 17. 5 18. 11 19. 108 20. 68 21. 6 4. Sample answer: D, E, C 5. 6.3 cm 6. 0.5 mm 7. 7.3 cm 8. 27 cm 9. 3 in. 10. 11. 12. 58 3 , 2 2 5 22. hexagon, convex, regular (1, 3) 13. 15 55 14. x 8, y 7 © Glencoe/McGraw-Hill 23. 174 24. 35 25. 21 B: length 11; width 4 A22 Glencoe Geometry Chapter 1 Assessment Answer Key Form 2D Page 45 Page 46 Sample answer: TU 1. Sample answer: T, U, V 2. 3. 15. 135°, obtuse 16. 6 17. 6 18. 7 19. 122 20. 32 RS 4. Sample answer: 5. 6. 7. 1 2 1 in. 4 1 in. Answers X, Y, Z 5.7 cm 8. 17 cm 9. 7 21. 9 22. 10. 65 pentagon, convex, regular 11. 32, 0 23. 185 24. 51 25. 68 B: 10, 18, 9 1 12. (1, 1) 250 13. 10 90 or 10 810 35.3 units 14. 2 © Glencoe/McGraw-Hill A23 Glencoe Geometry Chapter 1 Assessment Answer Key Form 3 Page 47 Page 48 planes ABCD, 1. BFCE, FBA, CDE, and plane P or ADEF 3 12. 15.5 x 8 13. 2. BC DC or 3. AE 15. 4. 1 1 in. 4 16. 5. 1 in. 8 27 14. 36 8 8.5 17. 6. 12.3 cm and 19.3 cm 7. 6 y D 8. 18. 8 B A C O 9. 20 or 25 4.5 2, 2, 1 10. (4, 1.5) 11. y 2, y 4 © Glencoe/McGraw-Hill x quadrilateral, concave, irregular 19. 9 20. B: A24 5 310 20.7 39 square: 9, triangle: 12 Glencoe Geometry Chapter 1 Assessment Answer Key Score General Description Specific Criteria 4 Superior A correct solution that is supported by welldeveloped, accurate explanations • Shows a thorough understanding of concepts involving special angle relationships, classification of angles, distance formula, regular polygons, angle bisectors, and perimeters. • Uses appropriate strategies to solve problems. • Computations are correct. • Written explanations are exemplary. • Graphs and figures are accurate and appropriate. • Goes beyond requirements of some or all problems. 3 Satisfactory A generally correct solution, but may contain minor flaws in reasoning or computation • Shows an understanding of the concepts involving special angle relationships, classification of angles, distance formula, regular polygons, angle bisectors, and perimeters. • Uses appropriate strategies to solve problems. • Computations are mostly correct. • Written explanations are effective. • Graphs and figures are mostly accurate and appropriate. • Satisfies all requirements of problems. 2 Nearly Satisfactory A partially correct interpretation and/or solution to the problem • Shows an understanding of most of the concepts involving special angle relationships, classification of angles, distance formula, regular polygons, angle bisectors, and perimeters. • May not use appropriate strategies to solve problems. • Computations are mostly correct. • Written explanations are satisfactory. • Graphs and figures are mostly accurate. • Satisfies the requirements of most of the problems. 1 Nearly Unsatisfactory A correct solution with no supporting evidence or explanation • Final computation is correct. • No written explanations or work is shown to substantiate the final computation. • Graphs and figures may be accurate but lack detail or explanation. • Satisfies minimal requirements of some of the problems. 0 Unsatisfactory An incorrect solution indicating no mathematical understanding of the concept or task, or no solution is given • Shows little or no understanding of most of the concepts involving special angle relationships, classification of angles, distance formula, regular polygons, angle bisectors, and perimeters. • Does not use appropriate strategies to solve problems. • Computations are incorrect. • Written explanations are unsatisfactory. • Graphs and figures are inaccurate or inappropriate. • Does not satisfy requirements of most problems. • No answer may be given. © Glencoe/McGraw-Hill A25 Glencoe Geometry Answers Page 49, Open-Ended Assessment Scoring Rubric Chapter 1 Assessment Answer Key Page 49, Open-Ended Assessment Sample Answers In addition to the scoring rubric found on page A25, the following sample answers may be used as guidance in evaluating open-ended assessment items. 1. A 4a. After drawing an acute angle, the student labels the vertex B and point A on one ray and point C on the other ray. Then the student uses a protractor to find the measure of ABC. The student lets the measure of ABC equal (6x 1) and solves for x. s B R C points A, B, and C 2a. After drawing a line on a coordinate grid, students should label two points on the graph D and G. b. To find the measure of an angle that is complementary to ABC, you would subtract mABC from 90. b. The students should use either the Pythagorean Theorem, the Distance Formula, or the Midpoint Formula to determine the distance between points D and G. c. To find the measure of an angle that is supplementary to ABC, you would subtract mABC from 180. 5a. c. Using the Midpoint Formula and the known coordinates for points D(x1, y1) and G(x2, y2), the coordinates of point H(x, y) can be found by solving for x xx 2 T (4x 6) R yy 2 and y in 1 x2 and 1 y2. (8x 6) S U is an angle bisector, then mTRS b. If RS and mSRU must be equal. Therefore, solve 4x 6 8x 6 for x. 4x 6 8x 6 6 6 8x 4x Add 6 and subtract 4x from 3a. The student draws a rectangle, labels the vertices W, X, Y, and Z, labels the width with a variable, such as x, and the length in terms of that variable, 3x 5. each side. b. An expression for the perimeter, where x is the width, would be either 2(3x 5) 2x or 8x 10. 12 4x 3x Combine like terms. Divide each side by 4. c. When x 7.5, mTRS 4(7.5) 6 and mSRU 8(7.5) 6. Simplifying each expression results in mTRS 36 and mSRU 8(7.5) 6 54. Since the and sum of the two measures is 90, RU RT must be perpendicular. c. Solving 58 8x 10 for x, the width is found to be 6 mm. To check that this answer is correct, use the value of the width to determine the length, 23. The sum of all four sides, 23 23 6 6, should equal 58. d. After using a ruler to draw a segment that is 23 mm long, students should label the endpoints P and Q. e. A measurement of 23 mm for P Q is accurate to within 0.5 mm. So, a measurement of 23 mm could be 22.5 to 23.5 mm. © Glencoe/McGraw-Hill A26 Glencoe Geometry Chapter 1 Assessment Answer Key Quiz 1 Page 51 Quiz 3 Page 52 1. RS , or RU or SU point S 3. points R, S, U or points T, S, V 2. 4. 1. perpendicular 2. complementary angle 3. 4. midpoint 5. vertical angles 6. 1 4 1 in. 5. 1 inch 8 6. 8.9 cm 7. 3 8. 33 in. 9. 4 10. C T obtuse U or V 23 1. 2. 3. 4. Sample answer: TSU and USV 5. TSU and WSP or 6. TSP and USW 7. 19 8. 12 9. 25 10. B angle bisector 7. supplementary 8. adjacent angles 9. acute angle 10. congruent Sample answer: 2. (4, 7) (3, 2) 3. 14 4. 40 1. Sample answer: Since 11. the measuring tool is 1 divided into -inch 2 increments, the measurement is precise to within 1 inch. Quiz 4 Page 52 Quiz 2 Page 51 4 12. Sample answer: Point M is between points P and Q only if P, Q, and M are collinear and PM MQ PQ. © Glencoe/McGraw-Hill 5. B A27 1. 2. 14 m 3. 86 units The perimeter is doubled. 4. 5. 4 Glencoe Geometry Answers Vocabulary Test/Review Page 50 Chapter 1 Assessment Answer Key Mid-Chapter Test Page 53 Cumulative Review Page 54 Part I 1. 2. 3. 4. B 1. A, C, and E or B, D, and F 2. C 3. 3 cm 4. 10 mm 5. 26 units 6. B(7, 1) C B C vertex: N; sides: NJ 7. and NK ; 90; right 5. D 8. vertex: N; sides: NK ; 100; obtuse and NH AFB and FCD or 9. EFG and FCD or CFD and CDG Part II 6. 37 7. 12, 1 8. (0, 3) 9. 3 10. 74 units 10. AFE and BFD 11. AFB or EFG 12. 7 13. quadrilateral; concave; irregular 17.1 units 14. 10 50 15. © Glencoe/McGraw-Hill A28 18 cm Glencoe Geometry Chapter 1 Assessment Answer Key Standardized Test Practice 1. 2. A E Page 56 B F C G D 11. H 13. 3. 4. A E B F C G 15. 5. A B C E F G H 7. A B C D E F G / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 14. 1 1 . / . / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 8 . 9 . / . / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 2 0 . / . / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 5 5 D 6. 8. . / . D H 12. 2 . / . / . . 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 16. 20 units 17. 81.5 units 18. 21 units H 9. A B C D 10. E F G H © Glencoe/McGraw-Hill A29 Glencoe Geometry Answers Page 55