2. circle - set of all points in a plane at a given distance from a given point in the plane

3. Parts of a Circle:

4. radius - segment from point on circle to circles center

5. center - point in middle of circle with letter next to it

6. Circles are named by their center point.

7. This circle is circle A.

8. What is the name of the circle below?

9. Circle N

10. congruent circles - circles with the same radius

11. These circles are congruent.

12. arc of a circle - two points on the circle and the unbroken part between the two points

13. arc of a circle endpoints - the two points that define an arc

14. NAMING ARCS An arc is named by its endpoints.

15. THREE TYPES OF ARCS: semicircle - arc whose endpoints are a diameter (half a circle)

16. THREE TYPES OF ARCS: semicircle - named using three points on the arc; endpoints listed first and last

17. THREE TYPES OF ARCS: The blue dashed arc is arc AOB or symbolically...

18. THREE TYPES OF ARCS: minor arc - arc less than a semicircle

19. THREE TYPES OF ARCS: minor arc - named using the two endpoint letters

20. THREE TYPES OF ARCS: The blue dashed arc is arc YZ or symbolically...

21. THREE TYPES OF ARCS: major arc - arc greater than a semicircle

22. THREE TYPES OF ARCS: major arc - named using three points on the arc with endpoints listed first and last

23. THREE TYPES OF ARCS: major arc - named using three points on the arc with endpoints listed first and last

24. THREE TYPES OF ARCS: The blue dashed arc is arc YXZ or symbolically...

25. chord A segment whose endpoints are on the circle.

26. AB is a chord.

27. diameter A chord that goes through the center of a circle.

28. CD is a diameter.

29. secant -line that goes through two points of a circle.

30. -line m is a secant

31. tangent -line that touches circle at only one point

32. -line p is a tangent

33. inscribed angle -angle made of two chords

34. -  ABC and  BCD are inscribed angles

35.  BCD is an inscribed angle m  BCD = ½ m

36. central angle -angle made of two radii

37. -  COD is a central angle

38.  COD is a central angle m  COD = m

39. Name each circle part as either a chord, diameter, secant, tangent, or inscribed angle.

40. tangent line

41. chord

42. secant

43. central angle  DOA

44. diameter

45. inscribed angle