The sum of either pair of opposite angles of a cyclic quadrilateral is `180^0` OR The opposite angles of a cyclic quadrilateral are supplementary.

Explanation

To prove that the sum of either pair of opposite angles of a cyclic quadrilateral is \(180^\circ\), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Cyclic Quadrilateral**:
Let's denote the cyclic quadrilateral as \(ABCD\). By definition, a cyclic quadrilateral is one where all vertices lie on the circumference of a circle.

2. **Label the Angles**:
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