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Math Help - Rectangle expressions, formula and graphing

  1. #1
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    Rectangle expressions, formula and graphing

    `

    I think the wording of the question throws me, I wondering if someone can have a look at what I have come up with and tell me if I am on the right track.

    For (a) all I can think of is X < L

    For (b) I get

    A = X * (100 - X) / 2


    Graphing this I get a parabola which I would expect.


    For (d) even without looking at the graph I know the width can't exceed the length

    so I assume x = 49.9 at its largest area as when x is 50 the length is then 50 and its

    a square.

    Knowing that then the dimensions for the largest possible area would be 49.9 X 50.1


    I apologize if all that is astronomically incorrect but any input would be greatly appreciated.
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  2. #2
    Senior Member
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    I'll get you started.

    If you ignore the context of this question, we have a 3 sided rectangle. 2 of the sides are x metres and you have 100 metres of wire netting. Wouldn't the other length be  100-2x ?
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  3. #3
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    Thanks for your reply so as the question states that one side is a pre existing wall, I

    understand what you said but the problem I have is the equation does not say

    whether it is the wall opposite X that is existing or the one opposite the length.



    What I got for the area I assume would depend on which one it is ie:

    If it where opposite x I get = A = X * (100 - X) / 2

    If it was one of the lengths = A = X * (100 - 2X)
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