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Homework Help: Modulus n00b

  1. Feb 28, 2005 #1
    1a
    Solve for x:
    |3x+2|=2|3-x|

    Done that part

    b
    Sketch the graph of y=|2x|-|3-x| and hence find all solutions of
    |2x|=|3-x|+2

    I have sketched the graph however I dont know what to do for "and hence find all solutions of
    |2x|=|3-x|+2"

    Please help :D Any help would be much appreciated
     
  2. jcsd
  3. Feb 28, 2005 #2
    Set y = 2 in your graph, and you'll arrive at the same equation. Draw a horizontal line at y = 2 and see where it crosses the graph.
     
  4. Feb 28, 2005 #3
    intersects at (1.6666666666666,2) and (-5,2)
     
  5. Feb 28, 2005 #4
    Correct. So x = 5/3 or x = -5. Check it against the equation.
     
  6. Feb 28, 2005 #5
    ah k coolies :D
     
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