Which of the following are models for perpendicular lines :
The line segments forming the letter 'L'.

Answer

To determine whether the line segments forming the letter 'L' are models for perpendicular lines, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Lines**: The letter 'L' consists of two line segments. One line segment is vertical (up and down), and the other is horizontal (side to side).

2. **Visualize the Angle**: When you draw the letter 'L', the vertical line meets the horizontal line at a certain angle.

3. **Measure the Angle**: The angle formed between the vertical and horizontal line segments is crucial. In this case, it is a right angle.

4. **Right Angle Definition**: A right angle is defined as an angle that measures exactly 90 degrees.

5. **Conclusion**: Since the angle formed by the two line segments of the letter 'L' is 90 degrees, we can conclude that the line segments forming the letter 'L' are indeed models for perpendicular lines.

### Final Answer:
Yes, the line segments forming the letter 'L' are models for perpendicular lines because they form a right angle (90 degrees).