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Homework Help: Small calculation help

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

    i have the answer for this i just don't know how it happened
    Issue1:
    2x+y+3=0
    x= -3

    Issue2:
    x+2y-3=0
    y=3

    2. Relevant equations

    How did they come up with this solution?

    3. The attempt at a solution

    I reread it & try to solve it no luck :(
     
  2. jcsd
  3. Jan 23, 2010 #2
    oh never mind i figured it out, it's a system of linear equation

    2 1 3
    1 2 -3

    solve the system the above results will come up. thank you forum
     
  4. Jan 23, 2010 #3

    Mentallic

    User Avatar
    Homework Helper

    You know how to solve matrices but not a system of 2 linear equations in 2 variables?
    You have essentially started with the harder stuff and skipped the easier ones :bugeye:
     
  5. Jan 23, 2010 #4
    My math skills are bad, i'm just working hard to pass these classes because i'm a computer science student. i finished all my major except 3 math courses which i am having the worst experience of my life in.
     
  6. Jan 23, 2010 #5

    Mark44

    Staff: Mentor

    If you're working with an augment matix, it should be
    Code (Text):

    [2 1 | -3]
    [1 2 | 3]
     
    The rows in this matrix come from these equations:
    2x + y = -3
    x + 2y = 3
     
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