What Is the Slope Formula?

The formula for finding the slope of a line on a coordinate plane is (y2 – y1) / (x2 – x1), where (x2, y2) and (x1, y1) represent two distinct points on the line. This is also known as “change in y over change in x” or “rise over run.”

For example, if the points (1, -4) and (-4, 2) both lay on the same line, the slope of that line equals (2 – -4) over (-4 – 1), or 6 over -5. Since a straight line has only one slope, the slope of the line is -6/5 regardless of which points on the line are plugged into the slope formula.