(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A rectangle has sides on the x and y axes and a corner on the plane x+3y=12. Find its maximum area.

2. Relevant equations

A=xy=(12-3y)y

(A=12, according to the solution manual.)

3. The attempt at a solution

At first I thought the corner it was talking about lay on one of the axes, but now I realize that it is a point around (4,3). I know there is a derivative (partial?) I need to take, but I don't know which one and or what to do it with respect to. I've drawn a graph so I can see what I'm doing, but the professor just skimmed over maximixation and I'm really confused! This chapter is not at a point that Lagrange multipliers have been covered. That's the way I would expect to do it, obviously not.

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# Homework Help: Maximizing area

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