Answer:
Step-by-step explanation:
Remark
Assume all of the sheet of plywood is to be used.
Front and back = 2 * 2x *h
Top and Bottom = 2 * 2x * x
Left/Right side = 2 * x * h
Total area = 4xh + 4x^2 + 2xh
Total area = 6xh + 4x^2
Total area = 600
6xh + 4x^2 = 600
h = (600 - 4x^2)/6x
h = 100/x - 2/3 x
Volume = x * 2x * h
Volume = 2x^2 * (100/x - 2/3 x)
Volume = 200x - 4/3 x^3
I can do this without calculus (I think), but it is much easier to use it.
dV/dx = 200 - 4x^2
This is a maximum when dV/dx = 0
dV/dx = 200 - 4x^2 = 0
4x^2 = 200
x^2 = 50
x = 5√2
