Triangle Sum Theorem & Exterior Triangle Theorem

Front

What is the Triangle Sum Theorem?

Back

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

Front

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

Back

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

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 one exterior angle of a triangle measures 120 degrees, and one of the non-adjacent interior angles measures 50 degrees, what is the measure of the other non-adjacent interior angle?

Back

The other non-adjacent interior angle measures 70 degrees (120 - 50 = 70).

Front

What is the relationship between the angles in a right triangle?

Back

In a right triangle, one angle is 90 degrees, and the sum of the other two angles is 90 degrees.

Front

If a triangle has angles measuring 33 degrees and 57 degrees, what is the measure of the third angle?

Back

The third angle measures 90 degrees (180 - 33 - 57 = 90).

Front

How do you find the measure of an angle when given the measures of the other two angles in a triangle?

Back

Subtract the sum of the two known angles from 180 degrees.

Front

What is the measure of an exterior angle if the two non-adjacent interior angles are 40 degrees and 60 degrees?

Back

The exterior angle measures 100 degrees (40 + 60 = 100).

Front

If the angles of a triangle are in the ratio 2:3:4, what are the measures of the angles?

Back

The angles measure 40 degrees, 60 degrees, and 80 degrees.

Front

What is the sum of the angles in any triangle?

Back

The sum of the angles in any triangle is always 180 degrees.