Question

in square ABCD sod ebc|| side AD , side AB = side DC​

Answer 1

Step-by-step explanation:

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>>In ABCD, side BC side AD, side AB

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In □ABCD, side BC∥ side AD, side AB≅ side DC If ∠A=72

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then find the measure of ∠B, and ∠D

Medium

Solution

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side BC∥ side AD

Interior angles on the same side of the transversal are supplementary.

∠A+∠B=180

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⇒72

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+∠B=180

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⇒∠B=180

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−72

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⇒∠B=108

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Construction:

Draw BP ∥⊂D

So,BC∥AD and BP∥CD

⇒PBCD is a parallelogram

⇒CD≅BP

Now CD=BP and CD=AB

⇒BP=AB

⇒∠BAP=∠BPA=72

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BP∥CD so,

∠CDP=∠BPA=72

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(corresponding angles are equal)

∠B=108

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∠D=72

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