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MATLAB 3 equations and 3 unknowns

  1. Mar 24, 2013 #1
    Hello,

    I have never really used MATLAB before, and I was assigned some homework on it. While I was able to solve most of them, I was unable to solve this one in particular, even after searching the internet and documentation, there was many kinds that I was left confused.

    Does anyone know the syntax for this general case:

    ax+by+cz=d
    ex+fy+gz=h
    ix+jy+kz=l (<- awesome I got vector components to match with x,y,z)

    And I'd like to solve for x, y, z.

    This is what I tried:

    A = [a,b,c;e,f,g;i,j,k]
    b = [d;h;l]

    and then A/b.

    This gives me three numbers (in my case, I'm not using letters)

    Is this the correct approach?

    All help is appreciated.
     
  2. jcsd
  3. Mar 24, 2013 #2
    Hello,

    I think the correct way is A\b , which is equivalent to inv(A)*b.

    Have a good day,
    J.
     
  4. Mar 24, 2013 #3
    You could use
    Code (Text):
    rref([A b])
    If there is a unique solution, the answer should be the identity matrix with an extra column on the right, which contains the solutions for x, y, and z.
     
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