Well we could do this even without looking at the graph. If I were to just make a table here where if this is x and this is y is equal to x squared, when x is equal to one, y is equal to one squared, which is just one. You see that right over there. And when x is equal to three, y is equal to three squared, which is equal to nine. And so you can see when x is equal to three, y is equal to nine. And to figure out the average rate of change of y with respect to x, you say okay, well what's my change in x? Well we can see very clearly that our change in x over this interval is equal to positive two.