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Homework Help: Need help with Simulatneous Equation

  1. Sep 26, 2007 #1
    Need help with Simulatneous Equation....

    1. The problem statement, all variables and given/known data

    I have a circuit involving nodal analysis. I have the correct nodal equation just need help solving it.

    v1(1/r1 + 1/r2 + 1/r3) - 10v(1/r1) - v2(1/r3) = 0

    v2(1/r3 + 1/r4) - v1(1/r3) = 2A

    V2 and V1 are my two unknowns. I don't want the answer just a start would be helpful.
  2. jcsd
  3. Sep 26, 2007 #2

    Two equations, two unkowns.
    Treat the equations as a system of two equations with two variables.
    That should remind you about how you learned to solve systems of equations in algebra, recall that procedure and apply.


  4. Sep 26, 2007 #3

    D H

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    Staff Emeritus
    Science Advisor

    Use one of the equations to express v2 in terms of v1 (or vice-versa). Now replace the v2 in the other equation with this expression. This will yield an equation for v1 alone. Solve for v1, and finally solve for v2 using the equation for v2 in terms of v1.
  5. Sep 26, 2007 #4
    if r1=10, r2=50,r3=20,r4=100

    Should I get v2:(2A+v1(.05))/.06 for equation 2?
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