you originally start at the origin, (0,0), however the +2 moves your y value 2 places up. Start at (0,2), and then count your slope. 73/1 is a steep slope, but if thats correct, you would go up 73 units and over 1. making your next point (1,75). and do it the opposite way to make (-1,-71). there is 3 points for your graph.