The solution to a system of equations happens when

The longer leg of a 30° 60° 90° triangle is 16 times square root of three how long is a shorter leg

Can someone explain to me how to do

Use the method of cylindrical shells to find the volume v generated by rotating the region bounded by the curves about the given axis.y = 7ex, y = 7e^-x, x = 1; about the y-axis