Question 304628
Let the length of square be x feet

you are cutting off 2 feet from opposite sides. 
On a  length you are removing 4 feet

The length of the box will be x-4. So the width.

The height will be 2 feet , the length of the cut portion

Volume of cube = L*W*H

(x=4)*(x-4)*2

2*(x-4)^2= 32

(x-4)^2= 16

x-4 = 4

x=8

The square sheet of metal must be 8 feet