Triangle Sums

Front

What is the Triangle Sum Theorem?

Back

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

Front

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

Back

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

Front

What is the measure of each angle in an equilateral triangle?

Back

Each angle in an equilateral triangle measures 60°.

Front

What is the sum of the interior angles of a triangle?

Back

The sum of the interior angles of a triangle is 180°.

Front

If two angles of a triangle are 45° and 55°, what is the measure of the third angle?

Back

The third angle is 80° (180° - 45° - 55° = 80°).

Front

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

Back

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

Front

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

Back

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

Front

If one angle of a triangle is 30° and the other is 60°, what is the measure of the third angle?

Back

The third angle is 90° (180° - 30° - 60° = 90°).

Front

What is the measure of the angles in a triangle if one angle is twice the second angle and the third angle is 20° more than the second angle?

Back

The angles are 40°, 20°, and 120°.

Front

What is the measure of an angle that is supplementary to a 70° angle?

Back

The supplementary angle is 110° (180° - 70° = 110°).