Pretest Review (Day 2) Reviewing skills needed to succeed in Geometry. Agenda 1. Warm Up 2. Review Homework 3. Review for Pretest (Day 2) #1-13. Homework Please get out your agenda and record tonight’s homework. Homework: 1. “Geometry –Review for PreTest” #15-26. 2. Parent Signature on Course Expectations. 3. REMINDER: PreTest is Monday, September 15. Learning Objectives Objectives 1. Identify and/or recognize: points, lines, segments, rays. 2. Identify special pairs of angles. 3. Find area and perimeter of a triangle. 4. Find the area and circumference of a circle. Warm Up The Coordinate Plane: Has 4 quadrants The origin is at (0,0) Coordinates are (x, y). x is horizontal coordinate, y is vertical coordinate Perimeter, Area, and Circumference Perimeter: The sum of the lengths of the sides of a polygon (called circumference for circles) Units of measurement: in, yds, ft, miles, meters, etc… Area: The number of square units a polygon encloses Units of measurement: in2, cm2, mi2, etc… Triangle: Area = 1 bh 2 h b Pythagorean Theorem Used to find the missing side length of a right triangle. MUST be used on a right triangle c is the hypotenuse, a and b are the legs of the right triangle 2 a + 2 b = 2 c Circle: Radius: r Diameter: d =2r Circumference: r Area: d Let’s Practice! Try Problems #1-5 with the person next to you. I will select some of you to put your answers on the board. Be ready! Solving a System of Equations with 2 variables: Example: Solve for x and y. y = 3x - 5 4x - 3y = -35 Since y is isolated in equation 1, we can use the substitution method. Substitute 3x-5 from the first equation in for y in the second. Then solve for x. Use this value to find y. Solving a System of Equations with 2 variables: Now, it’s your turn! Try #7 on your classwork. Check your answer with the person behind you. Simplifying Radicals A radical is in simplest form when the number under the radical sign has no perfect square factors other than 1. Example: 1. Try these: 2. 3. Solving Quadratic Equations using the Square Root Method 1. Isolate the term. 2. Take the square root of both sides. 3. Don’t forget the +/- Example: 1. Solve for x. Why? Let’s Practice! Complete #6-10 and #12 on the classwork. Be prepared to present and explain how you got your answers. Vocabulary Line: A series of points that extends in 2 opposite directions without end Can name a line by any two points on the line with a line above it, or by a single lower case letter. (Please note: In Geometry, it is important to use the correct notations!!) Use the following image to answer the question. 1. Name a line. Examples : AB, EF , CB, etc. Vocabulary Segment: part of the line consisting of 2 endpoints and all the points between them How you name a segment: Use the 2 endpoints with a straight line above. Ray: part of a line consisting of one endpoint and all the points of the line on one side of the endpoint How you name a ray: Endpoint must be first, then any other point on the ray; write an arrow pointing to the right above Examples: 1. 2. A B A B AB or AB or BA AC Read “segment AB” or “segment BA” Read “Ray AB” or “Ray AC”. DO NOT write Ray BA or Ray CA. Must name endpoint first!! C Angles: Complementary 2 angles that add up to 90˚ Supplementary: 2 angles that add up to 180˚ All straight angles form a line, therefore measure 180˚ Triangles: Let’s Practice. Complete #11 and #13 on your classwork. Compare your answer with the person to your right. Be prepared to explain your answer to the class. Don’t forget to use the proper notation! Nice work, Mathletes!