Objective: to explore the relationships of inscribed angles, central angles, and the intercepted arc

Materials: GSP

Procedures: class will complete assigmnent in the computer lab

________________________________________________________________________________

Name ___________________

Period ___________________

Computer Number _________

1. Define the following words

a) inscribed angle --

b) central angle --

2. Using GSP construct a circle with the center at point C. Points A and B lie on the circle.

3. Contruct central angle ACB.

4. Add point D on the circle so that major arc ADB is formed.

5. Construct inscribed angle ADB. The diagram below illustrates the circle.

6. Measure each of the following.

a) arc AB _________

b) angle ACB _______

c) angle ADB _______

d) How are a) and b) related? _________________________________

e) How are a) and c) related? _________________________________

7. Move point D to three other locations on the circle. Record your findings.

	arc AB	­ACB	­ ADB
a)
b)
c)

8. Move point B to three other locations on the circle. Record your findings.

	arc AB	­ACB	­ ADB
a)
b)
c)

9. Make a conjecture about the following:

a) the relationship between the measure of the inscribed angle and its intercepted arc.

b) inscribed angles that intercept the same arc.

10. What do you think is the measure of an angle inscribed in a semicircle?

Use GSP to test your conclusion.

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