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Homework Help: Max value of x+y (solving a linear system)?

  1. Apr 23, 2010 #1
    1. The problem statement, all variables and given/known data

    A line passes through (3,4). What is the maximum value of x+y?

    2. Relevant equations
    y = mx + b

    3. The attempt at a solution

    So I set up a system of equations, m3+b =4; b = Y; mX + b = 0. Then I plugged my values for X and Y into m3+b = 4..
    The weird thing is though... there is no maximum value of x+y?? It's just a line, x or y could go out further and further to infinity
    How should I solve this? Thanks
  2. jcsd
  3. Apr 23, 2010 #2
    As you say, the only solution that makes sense here is "infinity". Are you sure you have the question right?
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