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Basic simultaneous question - I am stuck, please explain the solution to this! Watch

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    Simultaneous equation:

    3x-2y=4
    2x+3y=-6

    So I multiplied the top by 3 and the bottom by 2 in order to get the Y's the same:

    9x-6y=12
    4x+6y=-12

    And then the signs are different, so you add them together and get:

    13x=0

    How do you do this one? Is it as simple as x=0, so then you substitute x=0 into the equation to find out y?

    Am I just derping?

    SOrry for the dumb question.
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    (Original post by blobbybill)
    Simultaneous equation:

    3x-2y=4
    2x+3y=-6

    So I multiplied the top by 3 and the bottom by 2 in order to get the Y's the same:

    9x-6y=12
    4x+6y=-12

    And then the signs are different, so you add them together and get:

    13x=0

    How do you do this one? Is it as simple as x=0, so then you substitute x=0 into the equation to find out y?

    Am I just derping?

    SOrry for the dumb question.
    A good way to test your solution is to put it back into both of the original equations. After all, that's what you're finding
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    (Original post by SeanFM)
    A good way to test your solution is to put it back into both of the original equations. After all, that's what you're finding
    I ended up with x=0 and y=-2, which seems to be correct. Thanks, I just derped and got confused - I forgot X could be 0 and it would still be solvable.
 
 
 
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