Show that if the diagonals of a quadrilateral bisect each other at right angles, then it is a rhombus.

Explanation

To prove that if the diagonals of a quadrilateral bisect each other at right angles, then it is a rhombus, we can follow these steps:

### Step 1: Understand the Given Information
We are given a quadrilateral ABCD where the diagonals AC and BD bisect each other at point O and intersect at right angles (90 degrees).

### Step 2: State What We Need to Prove
We need to prove that the quadrilateral ABCD is a rhombus, which means that all its sides are equal in length.

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