If the two sides of a pair of opposite sides of a cyclic quadrilateral are equal, prove that its diagonals are equal.

Explanation

To prove that the diagonals of a cyclic quadrilateral are equal when a pair of opposite sides are equal, we can follow these steps:

### Step-by-Step Solution

1. **Draw the Cyclic Quadrilateral**:
Let \( ABCD \) be the cyclic quadrilateral, where \( A, B, C, D \) are points on the circumference of a circle.

2. **Given Information**:
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