Interior and Exterior Angles of Triangles

Front

What is the Triangle Sum Theorem?

Back

The Triangle Sum Theorem states that the sum of all interior angles in a triangle is always 180°.

Front

What is an interior angle of a triangle?

Back

An interior angle is an angle formed inside a triangle by two sides.

Front

What is an exterior angle of a triangle?

Back

An exterior angle is formed by one side of a triangle and the extension of an adjacent side.

Front

How do you calculate the measure of an exterior angle?

Back

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

Front

If one angle of a triangle is 70° and another is 60°, what is the measure of the third angle?

Back

The third angle is 50° (180° - 70° - 60° = 50°).

Front

What is the relationship between interior and exterior angles?

Back

Each exterior angle of a triangle is equal to the sum of the two opposite interior angles.

Front

What is a remote interior angle?

Back

A remote interior angle is an interior angle of a triangle that is not adjacent to a given exterior angle.

Front

If angle A is 45° and angle B is 55°, what is angle C?

Back

Angle C is 80° (180° - 45° - 55° = 80°).

Front

What is the measure of an angle if the other two angles in a triangle are 90° and 45°?

Back

The measure of the third angle is 45° (180° - 90° - 45° = 45°).

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°.