Exterior Angle Theorem

Front

What is the Exterior Angle Theorem?

Back

The Exterior Angle Theorem states that the measure of an exterior angle of a triangle is equal to the sum of the measures of the two non-adjacent interior angles.

Front

If angle A is 62° and angle B is 54°, what is the measure of the exterior angle at vertex C?

Back

The exterior angle at vertex C is 62° + 54° = 116°.

Front

What is the relationship between an exterior angle and its adjacent interior angle?

Back

The exterior angle is equal to the sum of the two opposite interior angles, while the adjacent interior angle is supplementary to the exterior angle.

Front

If an exterior angle measures 130°, what is the sum of the two opposite interior angles?

Back

The sum of the two opposite interior angles is 130°.

Front

In a triangle, if one interior angle measures 40° and another measures 70°, what is the measure of the exterior angle adjacent to the 40° angle?

Back

The exterior angle adjacent to the 40° angle is 70° + 40° = 110°.

Front

What is the formula to find the measure of an exterior angle?

Back

The measure of an exterior angle = measure of interior angle 1 + measure of interior angle 2.

Front

If angle A = 25° and angle B = 35°, what is the measure of the exterior angle at vertex C?

Back

The exterior angle at vertex C is 25° + 35° = 60°.

Front

How do you set up an equation using the Exterior Angle Theorem?

Back

Set the exterior angle equal to the sum of the two non-adjacent interior angles, e.g., if exterior angle = x, then x = angle 1 + angle 2.

Front

What is the measure of angle A if the exterior angle is 150° and angle B is 70°?

Back

Angle A = 150° - 70° = 80°.

Front

If the exterior angle is 180° and one interior angle is 90°, what is the other interior angle?

Back

The other interior angle is 180° - 90° = 90°.