## Parametric form of a line

The parametric form of a line represents it using two vectors: an arbitrary point on the line and the direction vector :

By choosing a value for the scalar , we can reach any point on this line. We can show this graphically as follows:

### Example of a line

To find the parametric line equation given two points and , we only have to calculate the direction vector which we obtain by subtracting one point from the other:

(1)