Here is my math problem.
One side of a rectangle is 6 units larger than the other.
If the area of the rectangle is A, what is the length of the smaller side?
These are my answer choices...
A)(Square root(A - 9)) + 3
B)(Square root(A + 9)) - 3
C)Square root(A - 3))+ 6
D)Square root(A + 3))- 6
How do I do this? Note I also have graphing Calculator.
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Edited by Bistromathics: 4/18/2013 2:22:02 AMGraphing calculator aint' gon' help here. You're going to have to solve a quadratic equation, but you won't have the C coefficient to plug into the TI. Let's get started. Here's what we know: A = L x W L = W + 6 Let's substitute to get that pesky L out of there: A = (W + 6) x W A = (W^2) + 6W Well, shit. If it weren't for that squared term, we could've just solved here. Instead, it's time for... the QUADRATIC EQUATION WEEEEEEE!!!1!!!!1 (W^2) + 6W - A = 0 W = -6 + sqrt(36 + 4A)/2 Thankfully, we can simplify the radical. 4 is a factor we can pull out. Shall we? W = -6 + 2sqrt(9 + A)/2 Another step of simplification. 2 is a common factor. W = -3 + sqrt(9 + A) And we have our answer. B) sqrt(9 + A) - 3 Oops, forgot something. The quadratic formula has a +/- but I just put + so what gives? Well, for one, there are no negative answers in the choices. And, because of the context, that makes sense: you can't have a negative side length.
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Anybody here that can explain this to me?
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It's B.
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Bump I'm desperate....
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Anybody else can help?
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A=w*(w+6) A=w^2+6w You need the area of the rectangle if you want a better answer than (L-6).