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Thread: Solving Systems Using Elimination

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    Question Solving Systems Using Elimination

    How do you solve the following system using elimination!

    2x-3y=61
    2x+y=-7
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    Quote Originally Posted by amberkraidich View Post
    How do you solve the following system using elimination!

    2x-3y=61
    2x+y=-7

    $\displaystyle 2x-3y=61$

    $\displaystyle 2x+y=-7$

    subtract the 2nd equation from the 1st equation.


    $\displaystyle {2x-3y=61}$
    $\displaystyle \frac{-2x-y=7}{-4y=68}$

    $\displaystyle y=-17$

    then substitute

    $\displaystyle 2x-3(-17)=61$

    $\displaystyle 2x+51=61$

    $\displaystyle 2x=10$

    $\displaystyle x=5$

    then check:

    $\displaystyle 2x-3y=61$

    $\displaystyle 2(5) - 3(-17) = 61$

    $\displaystyle 61= 61$


    $\displaystyle 2x+y=-7$

    $\displaystyle 2(5) + (-17) = -7$

    $\displaystyle -7=-7$
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