Circle theorem applications & the Tangent-Chord Theorem.

1. Angles and chords
in so many places ...
circle of life by flickr user bitterlysweet

2. A
C
E B
F
D
15
12
Find AB
CD is a diameter

3. A C
B
O
D
3
2 Find BC
Find BD
DC = 2
OD = 3

4. 1
Find 1
110°
O
1
100°
>>
>> O
1
70°
40°

5. a°
O
a°
b°
b°