Triangle Angle Sum (Interior/Exterior)

Front

What is the Triangle Angle Sum Theorem?

Back

The Triangle Angle Sum Theorem states that the sum of the interior angles of a triangle is always 180 degrees.

Front

If one angle of a triangle measures 90 degrees, what can you say about the other two angles?

Back

The other two angles must be acute and their sum must be 90 degrees.

Front

What is an exterior angle of a triangle?

Back

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

Front

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

Back

Subtract the sum of the known angles from 180 degrees.

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 = 50 degrees and angle B = 60 degrees, what is angle C?

Back

Angle C = 180 - (50 + 60) = 70 degrees.

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 remote interior angles.

Front

If angle P is 60 degrees, what is the measure of the exterior angle formed at that vertex?

Back

The exterior angle is equal to 180 - 60 = 120 degrees.

Front

What is the measure of an angle if it is complementary to 30 degrees?

Back

The angle measures 60 degrees, since complementary angles sum to 90 degrees.

Front

What is the measure of an angle if it is supplementary to 120 degrees?

Back

The angle measures 60 degrees, since supplementary angles sum to 180 degrees.