Question 603460
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First off you cannot use *[tex \LARGE A(x)] because that says the function *[tex \LARGE A] depends on *[tex \LARGE x] when in fact the function *[tex \LARGE A] depends on both *[tex \LARGE x] and *[tex \LARGE y].


You can write:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ A(x,y)\ =\ xy]


But that doesn't do much for your specific situation where you want the area to be *[tex \LARGE 400\ ft^2]


The question you want to answer is: Given that the result must be a rectangle with an area of *[tex \LARGE 400\ ft^2], if I choose a value *[tex \LARGE x] for one of the dimensions of the rectangle, what must the other dimension, *[tex \LARGE y], be?


Start with

*[tex \LARGE \ \ \ \ \ \ \ \ \ \ xy\ =\ 400]


Divide by *[tex \LARGE x]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ y\ =\ \frac{400}{x}]


John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
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