1. Inscribed Angles

2. Inscribed Angles and Central Angles A Central angle has a vertex that lies in the center of a circle. A n inscribed angle has a vertex that lies on the edge of a circle and its two sides are chords of the circle.

3. Measurements of Central Angles T he measure of a central angle is equal to the measure of its intercepted arc. x°x° 80 280 T herefore the measure of angle X must be 80°.

4. Measurements of Inscribed Angles T he measure of an inscribed angle is equal to the half the measure of its intercepted arc. 80 280 T herefore the measure of angle X must be 40°. x°

5. Identifying Intercepted Arcs 1 Identify the Intercepted Arc for The intercepted Arc for 1

6. Identifying Intercepted Arcs 2 The intercepted Arc for 2 2

7. Identifying Intercepted Arcs 3 The intercepted Arc for 3

8. Making Conjectures 3 Make a conjecture about 2 They are congruent because they share the same intercepted arc.

9. Identifying Intercepted Arcs Identify the Intercepted Arc for The intercepted Arc for

10. Identifying Intercepted Arcs The intercepted Arc for

11. Determining Measures of Inscribed Angles Determine the measure of The measure of

12. Determining Measures of Inscribed Angles Determine the measure of The measure of

13. Determining Measures of Inscribed Angles Determine the measure of The measure of

14. Determining Measures of Inscribed Angles Determine the measure of The measure of

15. Determining Measures of Inscribed Angles Determine the measure of The measure of

16. Determining Measures of Inscribed Angles Determine the measure of The measure of

17. Determining Measures of Arcs Determine the measure of The measure of

18. Determining Measures of Arcs Determine the measure of The measure of

19. Determining Measures of Arcs Determine the measure of The measure of

20. Determining Measures of Arcs Determine the measure of The measure of

21. Determining Measures of Arcs Determine the measure of The measure of