#$&* course Phy 231 we can graph the change in velocity with respect to time. the y-axis is velocity and the x-axis time. If we plotted two dots on the graph, one at (2,5) and the other at (4,7), then connected the two dots, we could figure out what the line represented. First, we would need a slope of the line. The slope of a function is rise/run. Well it just so happens that the slope is velocity/time which is the same as the formula for acceleration (delta V/ delta T). So the line on the graph represents the average acceleration.