Q17 of 33 Page 108

In the parallelogram ABCD, ∠A :∠B = 3 : 2. Let us write the measures of the angles of the parallelogram.

Given,


∠A : ∠B = 3 : 2


Let ∠A = 3x


and ∠B = 2x



We know, In a parallelogram sum of adjacent angles is 180°


⇒ ∠A + ∠B = 180°


⇒ 3x + 2x = 180°


⇒ 5x = 180°


⇒ x = 36°


Now, ∠A = 3(36) = 108°


∠B = 2(36) = 72°


Also, Opposite angles of a parallelogram are equal


⇒ ∠A = ∠C = 108°


⇒ ∠B = ∠D = 72°


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