In trapezoid ABCD, sides AB and CD are paralllel, A = 2D and C = 3B + A. Find B.
In trapezoid ABCD, sides AB and CD are parallel, A = 2D and C = 3B + A. Find B.
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∠A + ∠D = 180º
2D + D = 180
∠A = 120º
∠D = 60º
∠B + ∠C = 180º
B + 3B + 2D = 180
4B = 60
B = 15