pick 2 sets of points....any 2 sets (25,-8),(30,-10) now we use the slope formula : (y2 - y1) / (x2 - x1) now we label our points... (25,-8).....x1 = 25 and y1 = -8 (30,-10)...x2 = 30 and y2 = -10 now we sub....play close attention to ur signs slope = (-10 - (-8) / (30 - 25) = (-10 + 8) / 5 = -2/5 <== ur slope
