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Math Help - College Algebra help

  1. #1
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    College Algebra help

    Solving systems with 3 variables:

    What is the value of y?

    5x - 3z = 26
    x - y - 2z = 3
    -5x + 3y - z = -3



    can someone please show me step by step how to solve this type of equation. I have had a few people show me but I am still not understanding the steps. Thanks.
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  2. #2
    MHF Contributor red_dog's Avatar
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    Add the first and the third equation:

    3y-4z=23

    Multiply the second with 5 then add with the third:

    -2y-11z=12

    Now we have the system:

    \left\{\begin{array}{ll}3y-4z=23\\-2y-11z=12\end{array}\right.

    Multiply the first equation by 11 and the second by -4, then add them:

    41y=205\Rightarrow y=5
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  3. #3
    Super Member
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    Quote Originally Posted by xbchgrl04x View Post
    can someone please show me step by step how to solve this type of equation. I have had a few people show me but I am still not understanding the steps. Thanks.
    I did show you step-by-step how to solve a problem like this in your earlier thread: http://www.mathhelpforum.com/math-he...variables.html. Can you tell me exactly which steps are you not understanding????


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