Question

In the figure, angle D measures 127° and angle A measures 75°.

Complete the equation to solve for b, the measurement of angle B.

Answer 1

Angles C and D are supplementary, or they add up to 180.

b = 180 - 75 - (180 - 127)

Hope this helps!

Answer 2

Explanation:

∠C + ∠D = 180 {Linear pair}

∠C + 127 = 180

∠C = 180 - 127

In ΔABC ,

∠A + ∠B + ∠C = 180 {angle sum property of triangle}

∠B = 180 - ∠A - ∠C

b = 180 - 75 - (180 - 127)