Answer
Net Change: $ 9$
Average Rate of change: $ 3$
Work Step by Step
From the equation $f(x) = x^2 - 2x$, we are looking from the net change and average rate of change from x=1 to x=4
At x=1, $f(x) = 1^2 - 2(1) = -1$
At x=4, $f(x) = 4^2 - 2(4) = 8$
Net Change: $f(4) - f(1) = 8 - (-1) = 9$
Average Rate of change: $\frac{f(4)- f(1)}{4-1} = \frac{9}{3} = 3$