Exterior Angles of a Triangle

Front

What is an exterior angle of a triangle?

Back

An exterior angle of a triangle is formed by one side of the triangle and the extension of an adjacent side. It is equal to the sum of the two opposite interior angles.

Front

What is the relationship between an exterior angle and the interior angles of a triangle?

Back

The measure of an exterior angle is equal to the sum of the measures of the two non-adjacent interior angles.

Front

If one interior angle of a triangle is 40°, what is the measure of the exterior angle adjacent to it?

Back

The exterior angle is 180° - 40° = 140°.

Front

How do you calculate the measure of an unknown angle in a triangle?

Back

To find an unknown angle in a triangle, use the fact that the sum of all interior angles in a triangle is 180°. Subtract the known angles from 180°.

Front

What is the sum of the exterior angles of any polygon?

Back

The sum of the exterior angles of any polygon is always 360°, regardless of the number of sides.

Front

If angle A = 62° and angle B = 36°, what is the measure of angle C in the triangle?

Back

Angle C = 180° - (62° + 36°) = 82°.

Front

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

Back

Exterior angle = Interior angle 1 + Interior angle 2.

Front

In a triangle, if one exterior angle measures 117°, what are the measures of the two opposite interior angles?

Back

The two opposite interior angles must sum to 117°.

Front

What is the measure of an exterior angle if the two opposite interior angles are 25° and 54°?

Back

Exterior angle = 25° + 54° = 79°.

Front

If angle A = 116° in a triangle, what is the measure of the exterior angle adjacent to angle A?

Back

Exterior angle = 180° - 116° = 64°.