# Precalculus Examples

,

Slope is equal to the change in over the change in , or rise over run.

The change in is equal to the difference in x-coordinates (also called run), and the change in is equal to the difference in y-coordinates (also called rise).

Substitute in the values of and into the equation to find the slope.

Simplify.

Simplify the numerator.

Multiply by .

Add and .

Simplify the denominator.

Multiply by .

Add and .

Divide by .

Use the slope and one of the given points such as to substitute for and in the point-slope form , which is derived from the slope equation .

Subtract from .

Simplify .

Subtract from .

Rewrite as .