1. Similar Right Triangles
If an altitude is drawn to the hypotenuse of a right triangle, then the two triangles formed are similar to the original triangle and to each other.
Identify the similar triangles in the diagram.

2. The “W” Pattern

3. Re-label the Sides

4. Geometric Mean #1
f is the geometric mean of d and e.

5. Geometric Mean #2
b is the geometric mean of e and c.

6. Geometric Mean #3
a is the geometric mean of d and c.

7. Put them all together

8. The “W” Pattern W

9. Try it !
d = 4
e = 10
Find:
a = ___
b = ___
c = ___
f = ___

10. Solution:
Proportions
Answers

11. Examples
Identify the similar triangles. Then find the value of x. 1. 2.