# Math Help - Volumes by Rotation

1. ## Volumes by Rotation

Find the volume of the solid that results when the region enclosed by y= the square root of x, y=0, and x=9 is revolved about the line x=9.

2. Originally Posted by kinana18
Find the volume of the solid that results when the region enclosed by y= the square root of x, y=0, and x=9 is revolved about the line x=9.
Use cylindrical shells in terms of x.

Your integral will be:

$\int\limits^{9}_{0} 2\pi (9-x)(\sqrt x) dx$