Can someone please explain the net change as well as help wi

Can someone please explain the net change as well as help with the answer.

The graph of a function is given. (a) Determine the net change between the indicated points on the graph. (b) Determine the average rate of change between the indicated points on the graph.

Solution

a)between points (0,6),(5,3)

net change = 3-6

net change = -3

b)

average rate of change =(3-6)_/(5-0)

average rate of change =-3_/5