Arc Measures

1. 10.2 Arc Measures
February 28, 2014
Be
llw
Give the name that best describes FD.
or
k
Chord
2. Is AB tangent to C? Explain.
3. Find x.
12
Yes; 162 + 30 2 = 1156 = 34 2
Feb 17­1:30 PM
HW pg. 661 #4­17
1

2. 10.2 Arc Measures
February 28, 2014
10.2 Arc Measures
Central Angle: angle's vertex is the center of circle
A
<ACB
C
B
Minor Arc: arc less than 180
A
minor arc AB
B
C
Major Arc: points not on the minor arc
A
major arc ADB
C
B
D
Semicircle: arc with endpoints of diameter
D
C
A
Semicircle AD
Measure of minor arc = measure of central <
A
C
mAB=50
50
B
Measure of major arc = 360 ‐ minor arc
A
C
D
mADB = 360 ­ 50= 310
50
B
Feb 17­1:46 PM
HW pg. 661 #4­17
2

3. 10.2 Arc Measures
February 28, 2014
Feb 17­3:57 PM
HW pg. 661 #4­17
3

4. 10.2 Arc Measures
February 28, 2014
Arc Addtion Postulate
A
C
B
mABD = mAB + mBD
D
Feb 17­3:59 PM
HW pg. 661 #4­17
4

5. 10.2 Arc Measures
February 28, 2014
Congruent Circles: same radius
Congruent Arcs: same measure in congruent circles
Feb 17­4:17 PM
HW pg. 661 #4­17
5

6. 10.2 Arc Measures
February 28, 2014
HW pg. 661 #4‐17
Feb 17­4:21 PM
HW pg. 661 #4­17
6