(x+4),(x+12),(x-1) and (x+5) are in proportion .find the value of x​

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(x+4),(x+12),(x-1) and (x+5) are in proportion .find the value of x​

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Hồng Cúc 5 years 2021-07-18T09:20:38+00:00 1 Answers 20 views 0

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  1. Giakhanh
    0
    2021-07-18T09:22:37+00:00
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    Answer:

    x = 16

    Step-by-step explanation:

    (x +4) : (x +12) ::  (x-1)(x +5)

    As they are in proportion,

    Product of means = Product of extremes

    (x + 4)* (x +5) = (x + 12)(x – 1)   {Use FOIL method}

    x*x +x*5 +4*x + 4*5 = x *x + x*(-1) +12*x + 12*(-1)

    x² + 5x + 4x + 20 = x² – x +12x – 12            {Now combine like terms}

     x² + 9x + 20  = x² + 11x -12

    x² + 9x +20 – x² – 11x = -12

    x² – x² + 9x – 11x     = -12 – 20          

        0   – 2x              = – 32

                           -2x = -32          {Divide both sides by -2}

                               x = -32/-2

                              x = 16

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