Two lines are said to be perpendicular if angle between them is _____

Options

A. `90^(@)`
B. `45 ^(@)`
C. `30^(@)`
D. None of these

Answer

To solve the question "Two lines are said to be perpendicular if the angle between them is _____", we follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Perpendicular Lines**:
- Perpendicular lines are defined as two lines that intersect at a right angle.

2. **Identify the Right Angle**:
- A right angle is an angle that measures exactly 90 degrees.

3. **Visualize Perpendicular Lines**:
- Draw two lines that cross each other, forming an "L" shape. The angle formed at the intersection is the right angle.

4. **Measure the Angle**:
- When the two lines intersect, the angle between them is measured. If the angle is 90 degrees, then the lines are perpendicular.

5. **Conclusion**:
- Therefore, we can conclude that two lines are said to be perpendicular if the angle between them is 90 degrees.

### Final Answer:
Two lines are said to be perpendicular if the angle between them is **90 degrees**.

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