1. Warm-up #2 (
Find x and m AD B
72o A C
9xo D

2. Table of Contents 29. Other Angle Relationships in Circles

3. Other Angle Relationships in Circles
Std – MM2G3 Understand properties of circles
Essential Question – What other angle/arc relationships are there in a circle?

4. Tangent and chord intersection
Where does a tangent and chord intersect?
Formula is the same as for inscribed angles.
m1 = ½ m AB B ( 1 A 2 C

5. Example:
Find m1 =
m2 =
m BCA =
75o
105o (
210o A 1 2
150o C B

6. Chord intersection (In the circle)
Angle = (arc + arc)/2
Arc + arc = angle * 2 B A 1 D C

7. Example: Find x. 80o ½ (40 + 120) ½ (160) = 80o x = 180 - 80 x = 100o

8. Tangent and secant intersection Out of the circle
Angle = (arc – arc) / 2
Arc – arc = angle * 2
Tangent and secant intersection Out of the circle B A X C

9. Example: Find x. 78 = ½ (204 – x) 360 – 80 = 280o 156 = 204 – x

10. Assignment
Pg. 624: 9-33 odd

11. Assessment
Pair and share