ABCD is a quadrilateral in which AB||DC and AD = BC. Prove that `angleA=angleB and angleC= angleD`.

Explanation

To prove that in quadrilateral ABCD, where AB is parallel to DC and AD = BC, we have angle A = angle B and angle C = angle D, follow these steps:

### Step 1: Draw the Quadrilateral
Draw quadrilateral ABCD such that AB is parallel to DC and AD = BC.

### Step 2: Extend Line AB
Extend line AB to a point E, making sure that the extension is straight.

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