Arc

1. 10.2 Arc Measures
HW pg. 661 #4­17
February 27, 2015
Give the name that best describes FD.
Chord
2. Is AB tangent to C? Explain.
3. Find x.
Yes; 162 + 302 = 1156 = 342
12
Bellwork

2. 10.2 Arc Measures
HW pg. 661 #4­17
February 27, 2015
10.2 Arc Measures
Central Angle: angle's vertex is the center of circle
Minor Arc: arc less than 180
Major Arc: points not on the minor arc
Semicircle: arc with endpoints of diameter
C
A
B
C B
A
D
C B
A
C
AD
minor arc AB
major arc ADB
<ACB
Measure of minor arc = measure of central <
C
A
B
50 mAB=50
Measure of major arc = 360 ‐ minor arc
C
A
B
50
D
mADB = 360 ­ 50= 310
Semicircle AD

3. 10.2 Arc Measures
HW pg. 661 #4­17
February 27, 2015

4. 10.2 Arc Measures
HW pg. 661 #4­17
February 27, 2015
Arc Addtion Postulate
D
C B
A
mABD = mAB + mBD

5. 10.2 Arc Measures
HW pg. 661 #4­17
February 27, 2015
Congruent Circles: same radius
Congruent Arcs: same measure in congruent circles

6. 10.2 Arc Measures
HW pg. 661 #4­17
February 27, 2015
HW pg. 661 #4‐17