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Find the dimensions of a rectangle with perimeter 40 with the largest area. (hint: Find an equation for area and one for perimeter, use both to find perimeter in terms of one variable)

  • math -

    let the width be x
    and the length be y

    2x + 2y = 40 or
    x+y=20 ---> y = 20-x

    Area = xy = x(20-x
    = 20x - x^2

    Are you in Calculus?
    Then the solution is very easy

    If not in Calculus, complete the square of this quadratic, again a very basic problem.

    Let me know what you get.

  • math -


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