If a line is perpendicular to one of the two given parallel lines then prove that it is also perpendicular to the other line.

Explanation

To prove that if a line is perpendicular to one of two given parallel lines, then it is also perpendicular to the other line, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Parallel Lines**: Let the two parallel lines be \( l_1 \) and \( l_2 \).

2. **Introduce the Perpendicular Line**: Let line \( m \) be a line that is perpendicular to line \( l_1 \). This means that the angle formed between line \( m \) and line \( l_1 \) is \( 90^\circ \).

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