Question

What is the measure of angle D?

Answer 1

52°

Explanation:

The trapezoid is a closed figure, meaning all the angles must equal 360°.

1. Set up the equation

128° + 126° + 54° + ∠D = 360°

2. Solve for ∠D

360 - 128- 126- 54 = 52

∠D = 52°

You can also solve this by knowing that in a trapezoid:

∠A + ∠D = 180° and ∠B + ∠C = 180°

1. Set up the equation

128 + ∠D = 180°

2. Solve

180 - 128 = 52

∠D = 52°

Answer 2

52

Explanation:

Since the sum of interior angles in a quadrilateral is 360°, you have to subrtact all those numbers from 360° in order to get angle D. What I mean is:

360 - (128+126+54)

360 - 308

52