Use the formula: slope = (y2 – y1) / (x2 – x1)
Identify two points on the line: (x1, y1) and (x2, y2)
Subtract the y-values
Subtract the x-values
Divide the change in y by the change in x
Simplify the fraction if possible
If the line is horizontal, the slope is 0
If the line is vertical, the slope is undefined