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

How do you calculate the measure of an exterior angle?

Back

To find the measure of an exterior angle, add the measures of the two opposite interior angles.

Front

If one interior angle of a triangle is 30° and another is 70°, what is the measure of the exterior angle?

Back

The exterior angle is 30° + 70° = 100°.

Front

What is the relationship between interior and exterior angles in a triangle?

Back

The sum of the measures of the interior angles of a triangle is always 180°, and each exterior angle is equal to the sum of the two opposite interior angles.

Front

If an exterior angle measures 120°, what are the possible measures of the two opposite interior angles?

Back

The two opposite interior angles must sum to 120°.

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

How can you use the Exterior Angle Theorem to solve for unknown angles in a triangle?

Back

You can set up an equation using the Exterior Angle Theorem to find unknown angles by equating the exterior angle to the sum of the two opposite interior angles.

Front

In a triangle, if one angle is 50° and another is 60°, what is the measure of the exterior angle adjacent to the 60° angle?

Back

The exterior angle is 50° + 60° = 110°.

Front

What is an example of a real-world application of the Exterior Angle Theorem?

Back

The Exterior Angle Theorem can be used in architecture and construction to determine angles when designing triangular supports.

Front

If a triangle has angles measuring 40°, 60°, and 80°, what is the measure of the exterior angle at the 80° angle?

Back

The exterior angle is 40° + 60° = 100°.