1.Previous
3.Next

points and , there is exactly one line that passes through them. There are several ways to write a linear equation of this line.

If , the slope of the line is Thus, a point-slope form is
:

By clearing denominators, one gets the equation
:which is valid also when (to verify this, it suffices to verify that the two given points satisfy the equation).

This form is not symmetric in the two given points, but a symmetric form can be obtained by regrouping the constant

1.Previous
3.Next