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Homework Help: Absolute value help

  1. Sep 13, 2011 #1
    1. The problem statement, all variables and given/known data

    |2x-8| + |12 - 3x | = 0



    2. Relevant equations

    what do i do when it = 0

    3. The attempt at a solution

    I tried solving it like all the others, but i know there is a unique thing to do when it = 0, i jus dont know what.

    So , heres what i did.

    2|x-4| + -3|x-4| = 0
    -|x-4| = 0

    x > 4

    (-)x-4 = 0
    -x = 4
    x = -4

    x < 4

    (-)-x+4 = 0
    x+4 = 0
    x = - 4.

    The answer is 4, I just probably set the normal one up wrong, what am i doing wrong?
     
  2. jcsd
  3. Sep 13, 2011 #2

    Mark44

    Staff: Mentor

    |12 - 3x | = |3x - 12| = 3|x - 4|
     
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