,

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.

Reduce the expression by cancelling the common factors.

Cancel the common factor of and .

Rewrite as .

Factor out of .

Reorder terms.

Factor out of .

Cancel the common factors.

Factor out of .

Factor out of .

Factor out of .

Cancel the common factor.

Rewrite the expression.

Add and .

Simplify the denominator.

Multiply by .

Add and .

Simplify the expression.

Multiply by .

Move the negative in front of the fraction.

The slope of a perpendicular line is the negative reciprocal of the slope of the line that passes through the two given points.

Cancel the common factor of and .

Rewrite as .

Move the negative in front of the fraction.

Multiply the numerator by the reciprocal of the denominator.

Multiply by .

Multiply by .

Multiply by .

Find the Slope of the Perpendicular Line to the Line Through the Two Points (-4,2) , (0,0)