In trapezoid ABCD, sides AB and CD are parallel, angle A = 2(angle D), and angle C = 8(angle B). Find angle B
Since AB and CD are parallel, BC is a transversal making angles B and C supplementary
So
B + C = 180
B + 8B = 180
9B = 180
B = 180 / 9 = 20°
Your so Smart
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