Triangle Angle Sum & Exterior Angle Theorem

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 is 90 degrees, what type of triangle is it?

Back

It is a right triangle.

Front

What is the measure of the third angle in a triangle if the other two angles are 41° and 59°?

Back

The third angle measures 80° (180° - 41° - 59°).

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 opposite interior angles.

Front

If one exterior angle of a triangle is 117°, what are the possible measures of the two opposite interior angles?

Back

The two opposite interior angles must sum to 117°.

Front

Solve for x: If angle A = 41° and angle B = 59°, what is angle C?

Back

Angle C = 80° (180° - 41° - 59°).

Front

What is the relationship between the angles in a triangle?

Back

The angles in a triangle are related such that their sum is always 180°.

Front

If angle A = 39° and angle B = 111°, what is angle C?

Back

Angle C = 30° (180° - 39° - 111°).

Front

Solve for x: If angle A = 90° and angle B = x, what is angle C?

Back

Angle C = 90° - x.

Front

What is the measure of an exterior angle if the two opposite interior angles are 39° and 69°?

Back

The exterior angle measures 108° (39° + 69°).