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Homework Help: System of equations

  1. Nov 17, 2008 #1
    1. The problem statement, all variables and given/known data
    I have 6 equations with six unknown variables. Does anyone know the best way to proceed?
    I've tried to substitute but it won't work for me.
    1.Ax+Bx+.03536F2=0
    2.Ay+Cy-212.1+.6124F2=0
    3.Bz+Cz-.7071F2-212.1=0
    4.-3Bz-4Ay+(5)*212.1+(5)*212.1=0
    5.4Ax+5Cz=0
    6.5Ax+3Bx-5Cy=0



    2. Relevant equations
    These are the forces in a bent rod supported at points A,B and C by journal bearings.
    equation 1 is[tex]\Sigma[/tex]Fx=0
    2 is [tex]\Sigma[/tex]Fy=0,etc.
    I don't need help with the statics, just with the solving for the unknown variables when so many are involved.
     
  2. jcsd
  3. Nov 17, 2008 #2
    Matrix equation. But even then, you're going to solve a 6x6 matrix. You make an equation of the form AX=B where B=0 (null matrix) in this case. X contains all your variables (x,y,z, etc) and A contains their coefficients.
     
  4. Nov 17, 2008 #3

    tiny-tim

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    Science Advisor
    Homework Helper

    Hi yoleven! :smile:
    You can simplify it a lot by starting with the easy one, #5, and then doing #1 and #3.

    Start it that way, and see what you get. :smile:
     
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