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Math Help - Please help me solve the following pair of simultaneous equations algebraically.

  1. #1
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    Please help me solve the following pair of simultaneous equations algebraically.

    Any non-integer solutions should be given as fractions in their simplest form.

    5a-b=9
    a+6b=-3

    Also, please show working.
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  2. #2
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    Start by multiplying the first equation by 6. Then add the two equations together to eliminate b.
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  3. #3
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    hi,
    what's next?
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  4. #4
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    Why not show what you have done and where you are stuck?
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  5. #5
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    I multiplied the first equation by 6
    and added the 2 equations together

    30a - b = 54
    a+6b = -3


    31 + b =51
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  6. #6
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    It should actually have been

    30a - 6b = 54

    a + 6b = -3.


    Now try adding the equations together. What do you get?
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  7. #7
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    Is it

    31a+12b=51?

    Thanks
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  8. #8
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    No, adding them gives:

    (30a - 6b) + (a + 6b) = 54 -3

    31a = 51

    b - b = 0
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