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February 13th, 2016, 09:48 AM   #1
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length times width and getting a new equation for area?

So here's my problem.

l = 52 - 2w

I need to write an equation for area based on width using the above equation. What am I missing here? Whatever the equation is, I have to enter it into my calculator to see the parabola, get the vertex, etc. I just can't figure out what the equation is I'm supposed to enter.

Any info would be appreciated. Thanks!
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February 13th, 2016, 09:50 AM   #2
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$A=lw$, and $l=52-2w$, so substitute.
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February 13th, 2016, 10:01 AM   #3
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Thanks. Still confused though!

We're using a word problem asking about 52 panels, each 1ft long. The back of a house will close in one side of the patio. The question is:

Generalize a model (equation) for calculating the length (l) in terms of the width (w).
Hint: work from perimeter: P=2l +2w

I'm assuming I'm right with the first part (l = 52 - 2w). But nothing I graph shows a parabola.
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February 13th, 2016, 11:16 AM   #4
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What is the exact problem statement (as worded by your instructor)? Include all given information.
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area, equation, length, times, width

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