1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Linear Algebra Question - Matrices

  1. Feb 4, 2008 #1
    The flow through acommunication circuit is modeled by the graph below. Solve the circuit.
    Let the face be a circut

    120 -----> :rolleyes: --x2--->:rolleyes: -----> 150
    ^ ^
    l x1 l x3
    l l
    340 -----> :rolleyes: --x4--->:rolleyes: -----> 310

    There is some formatting error with the x1 and x3, but x1 goes from the bottom left circuit to the top left circuit and x3 goes from the bottom right circut to the upper right circuit.

    I just wanted someone to check what I have done to make sure it is correct and that I haven't forgotten anything. Thanks!

    I have :
    120 + x1 = x2
    340 = x1 + x4
    x2 + x3 = 150
    x4 = 310 + x3

    Matrix
    -1 1 0 0 120
    1 0 0 1 340
    0 1 1 0 150
    0 0 -1 1 310

    after row reducing the matrix it comes out as
    1 0 0 1 340
    0 1 0 1 460
    0 0 0 -1 -310
    0 0 0 0 0

    The equations are
    x1 + x4 = 360
    x2 + x4 = 460
    x3 - x4 = 310

    Is this correct? Am I missing something? Thanks!
     
    Last edited: Feb 4, 2008
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you help with the solution or looking for help too?