If a line is drawn parallel to the base of an isosceles triangle to intersect its equal sides, prove that the quadrilateral, so formed is cyclic.

Explanation

To prove that the quadrilateral formed by drawing a line parallel to the base of an isosceles triangle is cyclic, we will follow these steps:

### Step-by-Step Solution:

1. **Draw the Isosceles Triangle**:
Let triangle ABC be an isosceles triangle where AB = AC. Let BC be the base.

2. **Draw the Parallel Line**:
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