If diagonal of a parallelogram bisects one of the angles of the parallelogram, it also bisects the second angle.

Explanation

To prove that if the diagonal of a parallelogram bisects one of the angles, it also bisects the second angle, we can follow these steps:

### Step-by-Step Solution:

1. **Given Information**: Let ABCD be a parallelogram where the diagonal AC bisects angle A. This means that angle A can be divided into two equal parts. Let's denote these angles as:
- Angle A = ∠1 + ∠2, where ∠1 = ∠2 (since AC bisects angle A).

2. **Identify Parallel Lines**: In parallelogram ABCD, we know that AB is parallel to DC (AB || DC).
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