Lines and Angles WebQuest
NAME:
Directions: Go through each of the following applets. Explore and experiment with each
applet. Answer the focus questions using complete sentences. Be prepared to
share what you learned while exploring these applets.
Use these websites to research information
http://www.ies.co.jp/math/products/geo1/menu.html
http://oneweb.utc.edu/~Christopher-Mawata/geom/geom1.htm
http://www.mrperezonlinemathtutor.com/Geometry_applets_by_Mr._Perez.html
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Geometric Objects
1. What is a point? Use your own words to describe.
2. What does “ JIH” mean?
3. How is a point different from a vertex?
4. What is the difference between a line, a ray, and a segment?
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Measuring with a protractor
5. How can you decide when to use the “small” numbers versus when to use the
“big” number?
6. A reflex angle is an angle that is larger than 180°. Describe how to measure such
an angle?
7. Estimate the measure  ABC for each figure. DO NOT USE A PROTRACTOR!
Lines and Angles WebQuest
Duane Habecker
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Complementary Angles
8. What does it mean when two angles are complementary?
9. Are 40° and 60° complementary to each other? Explain how you know.
10. Give an example of two angles that are complementary angles.
4
Missing Complementary Angle
11. If two angles are complementary, what does that mean?
12. Suppose two angles are complementary. If one angle has a measure of 62°, what
is the measure of the second angle?
13. Find m BCE for each of the following figures:
Lines and Angles WebQuest
Duane Habecker
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Supplementary Angles
14. If  ACD and  BCD are supplementary. Draw the angles below. What does it
mean when two angles are supplementary?
15. Are 50° and 130° supplementary to each other? Explain how you know.
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Missing Supplementary Angle
16. If  ACD and  BCD are supplementary, what does that mean?
17. Suppose two angles are supplementary. If one angle has a measure of 62°, what
is the measure of the second angle?
18. Find m BCD for each of the following figures:
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Sum of angles in a triangle
.
19. What is the sum of the angles in any triangle?
20. If you know the measure of two angles in a triangle, how can you find the third
angle?
21. Find the m C for each of the following triangles:
Lines and Angles WebQuest
Duane Habecker
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Missing Angles in Triangle with External Angle
This applet provides you with practice for finding the missing angles in a geometrical
figure.
22. Use this applet to create a problem and then find the measures of the missing
angles. Write step-by-step directions for how you found the missing angles.
Sketch the figure and show your work here.
23. Find the measures of the missing angles:
m ACE = 134°
m ECD = __________
m EDC = __________
m CED = 39°
m EDB = __________
24. Find the measures of the missing angles:
Lines and Angles WebQuest
Duane Habecker
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m ACE = 79°
m ECD = __________
m EDC = __________
Lines and Angles WebQuest
Duane Habecker
m CED = 38°
m EDB = __________
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