1. Tangents Section 10.5

2. Definition: Tangent  A tangent is a line in the plane of a circle that intersects the circle in exactly one point.

3. Tangent Radius Theorem  If a radius is drawn to the point of contact then the tangent is perpendicular to the radius.  If is tangent to circle P, then

4. Two Tangent Theorem  If two tangent segments are drawn to a circle from an external point, then those segments are congruent.  If are tangent and share point S as an endpoint, then

5. Example 1 Find x. Assume that all segments that appear to be tangent are tangent.  CD = 8, CE = 5  Decide which angle must be the right angle and set up Pythagorean Theorem  must be the right angle so

6. Ex. 2  Find x. Assume that segments that appear to be tangent are tangent.

7. Ex 3 Assume that all segments that appear to be tangent are tangent.  Find ST.

8. Ex 4  Is tangent to the circle? Why or why not?

9. Ex 5  Find the perimeter of the polygon given that all sides that appear to be tangent are tangent.

10. Homework:  Pg. 593 5 – 22, 37, 39 - 42