Triangle Sum and Exterior Angle Theorem

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

If angle A = 39° and angle B = 83°, what is the measure of angle C?

Back

Angle C = 180° - (39° + 83°) = 58°.

Front

What is the measure of an exterior angle of a triangle?

Back

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

Front

If angle X is an exterior angle and angle Y = 40° and angle Z = 60°, what is the measure of angle X?

Back

Angle X = 40° + 60° = 100°.

Front

What is the relationship between the angles in a triangle?

Back

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

Front

How do you find a missing angle in a triangle when two angles are known?

Back

Subtract the sum of the known angles from 180°.

Front

What is the formula to find the measure of an exterior angle?

Back

Exterior angle = Interior angle 1 + Interior angle 2.

Front

If angle A = 30° and angle B = 70°, what is angle C?

Back

Angle C = 180° - (30° + 70°) = 80°.

Front

What is the sum of the angles in a triangle?

Back

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

Front

What is the measure of angle Y if angle X = 50° and angle Z = 60°?

Back

Angle Y = 180° - (50° + 60°) = 70°.