1. Bell Ringer Write an example of each of the following: Radius ____
Secant ____
Tangent ____
Chord ____
Diameter ____
Minor arc ____
Major arc ____
Central angle ____
Inscribed angle ____
Center ____

2. Quick Review of Definitions
Arc Length
Wednesday, May 4, 2016
Quick Review of Definitions

3. Chord
a segment whose endpoints lie on a circle A B AB

4. Arc
an unbroken part of a circle

5. Minor Arc an arc that is less than half of a circle
to name, use 2 points

6. Major Arc an arc that is more than half of a circle
to name, use 3 points

7. Central Angle
an angle whose vertex is at the center of a circle

8. Inscribed Angle
an angle whose vertex is on a circle and whose sides are chords of the circle

9. Tangent
a line, ray, or segment that is in the same plane as the circle, but intersects the circle in only one point

10. Secant
a line, ray, or segment that contains a chord

11. Arc Length
Arc Length is a portion of the circumference because everything is proportional when it comes to circles!
You need to know the central angle that intercepts your arc to set up your proportion.

12. Examples Find the arc length: 1. Radius 5cm, central angle 50o
Find the circumference:
3. Central angle 55o, arc length 5.5cm
4. Central angle 60o, arc length 3.82m
Find the central angle:
5. Arc length 45ft, radius 12ft
6. Arc length 30in, radius 14in

13. Assignments Classwork: Geometry book p. 686-688 #13-47 odd Homework:
Circumference and Arc Length

14. Exit Ticket
1. How does the proportion for arc length compare with the proportion for arc measure?
2. What is the difference between arc length and arc measure?