1. Homework Review

2. CCGPS Geometry Day 26 (9-12-13) UNIT QUESTION: What special properties are found with the parts of a circle? Standard: MMC9-12.G.C.1-5,G.GMD.1-3 Today’s Question: What other angle relationships do we know for circles? Standard: MMC9-12.G.C.2

3. TANGENT: a LINE that intersects the circle exactly ONE time

4. Point of Tangency

5. Two circles can intersect… in two points one point or no points

6. No points of intersection (different center)

7. No points of intersection (same center) Same center but different radii

8. 1 point of intersection (Tangent Circles) Internally Tangent Externally Tangent

9. 2 points of intersection

10. Common Tangents Internal

11. Common Tangents External

12. If a line (segment or ray) is tangent to a circle, then it is perpendicular to the radius drawn to the point of tangency. Point of Tangency More Pythagorean Theorem type problems! Yeah!!

13. a 2 + b 2 = c 2 x = 15 9 2 + 12 2 = x 2

14. a 2 + b 2 = c 2 RQ = 16 12 2 + (QR) 2 = (8+12) 2 12 2 + (QR) 2 = 20 2

15. No a 2 + b 2 = c 2 ?

16. R S T If two segments from the same exterior point are tangent to a circle, then they are congruent. Party hat problems!

17. R S T

18. R S T

19. A C E B D P

20. T S Q P N R