Prove that if the two arms of an angle are parallel to the two arms of another angle, then the angles are either equal or supplementary.

Explanation

To prove that if the two arms of an angle are parallel to the two arms of another angle, then the angles are either equal or supplementary, we can follow these steps:

### Step-by-Step Solution:

1. **Draw the Diagram**:
- Draw two angles such that the arms of the first angle are parallel to the arms of the second angle.
- Let the first angle be ∠ABC and the second angle be ∠DEF, where AB || DE and BC || EF.

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