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Homework Help: 10 -2x = 90 - x

  1. Dec 10, 2009 #1
    I can't work this one out. I need to find the vlaue of x

    10 -2x = 90 - x

    I come up with 3x = 80 which I know is wrong. This is how I get there:

    10 -2x = 90 - x
    10 -3x = 90
    3x = 80

    The actual answer is x= -80. Where am I going wrong?
     
  2. jcsd
  3. Dec 10, 2009 #2

    itr

    User Avatar

    10-2x=90-x
    10-x=90
    -x=80
    x=-80
     
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