2.8a Angle Addition Postulate

Front

What is the Angle Addition Postulate?

Back

The Angle Addition Postulate states that if point D is in the interior of angle ABC, then m∠ABD + m∠DBC = m∠ABC.

Front

If m∠ABC = 103°, what is the measure of angle ABD if m∠ABD = 15°?

Back

m∠DBC = m∠ABC - m∠ABD = 103° - 15° = 88°.

Front

Given m∠QST = 135°, what is the equation to find x if m∠QSR = 3x + 1 and m∠RST = 2x - 6?

Back

3x + 1 + 2x - 6 = 135.

Front

What is the measure of angle EFG if m∠EFG = 37° and m∠FGH = 19°?

Back

m∠EFG + m∠FGH = m∠EHG; m∠EHG = 37° + 19° = 56°.

Front

If m∠A + m∠B = 90° and m∠A = 49°, what is m∠B?

Back

m∠B = 90° - m∠A = 90° - 49° = 41°.

Front

What is the relationship between complementary angles?

Back

Two angles are complementary if the sum of their measures is 90°.

Front

What is the relationship between supplementary angles?

Back

Two angles are supplementary if the sum of their measures is 180°.

Front

If m∠XYZ = 90° and m∠XZY = 45°, what is m∠YZX?

Back

m∠YZX = 90° - m∠XZY = 90° - 45° = 45°.

Front

What is the formula to 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 non-adjacent interior angles.

Front

If m∠PQR = 60° and m∠QRS = 40°, what is m∠PRS?

Back

m∠PRS = m∠PQR + m∠QRS = 60° + 40° = 100°.