The average rate of change is the slope. If we were looking for the instantaneous rate, we would be doing calculus. This is a curve; therefore, the average rate of change is not going to give you the exact slope, because slope is most beneficial to straight lines. But nevertheless, take the x and y coordinates for the distance in question, which are (0, 1) and (2, -3). Putting these into the slope formula will give us
which is a slope of -2. That's the average rate of change. When you get to calculus you will be able to find the instantaneous rate by finding the derivative.