Let g(x)=$\displaystyle \int_0^x f(t)dt$, where f is the function whose graph is shown.

g(0) = 0

g(3) = 4.5

g(6) =

g(9) =

g(12) =

g(15) =

g(18) =

I got the first two, but I guess I am just not getting the rest, if you could help me with how to set the up the others.

I thought g(6) you would take the 4.5 and subtract the area of the triangle that goes below the x-axis to give you -9, but the computer is telling me thats wrong. Please help!