How would you denote a line which has two points M and N on it?

Answer

To denote a line that passes through two points M and N, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Points**: First, we need to identify the two points on the line. Let's say we have point M and point N.

2. **Draw the Line**: Next, we can draw a straight line that passes through both points M and N. This line can extend infinitely in both directions.

3. **Notation**: To denote the line that passes through points M and N, we use the notation:
- Line MN or \( \overleftrightarrow{MN} \)
- This notation indicates that the line extends infinitely in both directions through points M and N.

4. **Labeling**: It is also helpful to label the points on the line clearly, so we can refer to them easily.

### Final Notation:
Thus, the line that passes through points M and N can be denoted as \( \overleftrightarrow{MN} \).

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