Here's the problem. I just have difficulty figuring out the problems where you are revolving a shape around something other than the x or y-axis. Any help would be greatly appreciated.

Here's the full problem:

Use the shell method to find the volume of the solid generated by revolving the plane region about the given line.

$\displaystyle y=x^2$, $\displaystyle y=4x-x^2$, about the line $\displaystyle x=4$