1. Using Similar Right Triangles
Use properties of the altitude of a right triangle

2. Theorem
If the altitude is drawn from the vertex of the right angle of a right triangle to its hypotenuse, then the two triangles formed are ~ to the given triangle and to each other. D A C B 2

3. Theorem
The measure of the altitude drawn from the vertex of the right angle of a right triangle to its hypotenuse is the geometric mean between the measures of the two segments of the hypotenuse. 3

4. Example
Answer: CD is about 12.7. 4

5. Example
Answer: about 8.5 5

6. Theorem
If the altitude is drawn to the hypotenuse of a right triangle, then the measures of a leg of the triangle is the geometric mean between the measures of the hypotenuse and the segment of the hypotenuse adjacent to that leg. 6

7. Example
Find c and d in
Answer: 7

8. Put this in your agenda
Pg 453
8-18, 21-26
Homework 8