Optimization Problem: Minimizing rectangle dimensions

Kenny Bala
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Hi guys, I'm a high school senior currently in calculus and vectors. We're in our application unit right now, and I'm having quite a bit of trouble with problems that give the desired volume/area, and then ask you for the minimum dimensions required for said volume. One notable problem that I am unable to figure out can be seen here: http://prntscr.com/6qcz7c

Could you guys give feedback on the problem and if possible, explain a general method of determining minimum dimensions? I can work with having dimensions given to me, but not with volume given instead.
 
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Sorry, Kenny, according to the Rules at PF, we can only offer assistance to those who make an attempt at solving their problems first.

You should make your best attempt, show us what you've done, and tell us where you are getting stuck.

Your problem states that the enclosure has a volume of 144 m2, which must be a typo, since volume is measured in cubic meters.

It's not clear why you can't work with a stated volume. Don't you know how to calculate the volume of a rectangular enclosure using the length, width and height?
 
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