Veronica is mulching her front yard. The total weight of mulch varies with the number of bags of mulch what is the rate of change?

I saw the graph that should have accompanied this problem.

y axis = weight in pounds; intervals of 30.

x axis = number of bags, intervals of 1.

Since the graph forms a line, the rate of change is constant. y = kx

x y

1 30

2 60

3 90

4 120

5 150

Rate of change = weight (lb) / bags = 30/1 or 30 pounds per bag.