Calc derivatives - Minimum total surface area in a box of V = 160 ft2

Dave_1420
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Hi everyone! I'm new to online math forums. I wonder if anyone can give me a hand on this - it would be greatly appreciated.

Thank you in advance!

Dave

Homework Statement



If a box with a square base and an open top is to have a volume of 160 cubic feet, find the dimensions of the box having the minimum total surface area. Use calculus to find the solution.

Homework Equations



If X are the sides of the base, and Y is the height of the box, what would be the formula to find surface? How can the minimum surface be calculated using derivative applications?

The Attempt at a Solution



Surface = minimum possible
 
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