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Math Help - What is the value of x - y - z?

  1. #1
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    What is the value of x - y - z?

    What is the value of x - y - z?

    x + y + z = 24
    x + y - z = 12
    x - y + z = 16
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  2. #2
    Senior Member OReilly's Avatar
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    Quote Originally Posted by Natasha1
    What is the value of x - y - z?

    x + y + z = 24
    x + y - z = 12
    x - y + z = 16
    From second equation we get
    z=x+y-12

    In third equation we replace z
    x-y+x+y-12=16
    2x=28
    x=14

    So we get now
    y+z=10
    y-z=-2
    -y+z=2

    From second equation we get y=z-2

    We replace y in first equation
    z-2+z=10
    2z=12
    z=6

    So we have x=14 and z=6 so we get that y=4.

    So x-y-z=14-4-6=4.
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