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algebra

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y varies directly with x. When y = 20, x = 50. Find x when y = 36.

  • algebra -

    y varies directly with x ----> y = kx , where k is a constant

    20 = k(50
    k = 2/5

    y = (2/5)x
    when y = 36
    36 = (2/5)x
    2x = 180
    x = 90

    or ... use a proportion

    x/50 = 36/20
    x = 50(36)/20 = 90

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