# Triangle Exterior Angle Theorem

- Author:
- bnewhous, Mathemeatic, Brian Hayes

1. Based off the above applet, in your own words how can you find the measure of an exterior an angle of a triangle?

**Triangle Exterior Angle Theorem**: The measure of an exterior angle of a triangle is equal to the sum of the measures of the two nonadjacent interior angles

2. Using the applet above, what is the relationship between an interior and exterior of triangle at the same vertex?

## Find the measure of angle CAD

3. Find the measure of angle CAD.

## 4. Find the measure of angle A.

Find the measure of Angle A

## 5. Find the measure of Angle QRF.

Find the measure of Angle QRF.

## 6. Find the measure of Angle AXY.

Find the measure of Angle AXY.

7. An exterior angle at the base of an isosceles triangle is always