What is the perimeter of the rectangle whose area =x^2+3x-40?

Question

What is the perimeter of the rectangle whose area =x^2+3x-40?

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Peyton 1 hour 2021-09-14T04:00:21+00:00 1 Answer 0

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    2021-09-14T04:01:31+00:00

    Answer:

    Perimeter = 4x + 6

    Step-by-step explanation:

    The area of a rectangle is given by:

    Area = L * W

    Where L is the length and W is the width.

    In this case, we need to factorate the area to find L and W:

    Area = x^2+3x-40

    Making Area = (x + a)*(x + b), we have:

    a * b = -40

    a + b = 3

    Solving this system, we have a = 8 and b = -5

    So we have Area = (x + 8)*(x – 5)

    So Length = x+8 and Width = x-5

    Perimeter = 2*L + 2*W = 2x + 16 + 2x – 10 = 4x + 6

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45:7+7-4:2-5:5*4+35:2 =? ( )