If the arms of one angle are respectively parallel to the arms of another angle, show that the two angles are either equal or supplementary.

Explanation

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

### Step-by-Step Solution:

1. **Draw the Angles**:
- Let angle 1 be formed by the arms AB and BC.
- Let angle 2 be formed by the arms DE and EF.
- Assume that AB is parallel to DE and BC is parallel to EF.
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