algebra

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i have 2 solve by elimination an i keep gettin fractions when the answer is (-3,-3)
my teacher gave me the answer an problem but she wants me 2 work it out
idk how i keep gettin fractions
the problem is:
-3x-4y=21
8x-5y=-9


please help

  • algebra -

    Multiply by -5 (-3x - 4y = 21)
    Multiply by 4 (8x - 5y = -9)

    15x + 20y = -105
    32x - 20y = -36
    47x + 0 = -141
    47x = -141
    x = -3

    8x - 5y = -9
    x = -3
    8(-3) - 5y = -9
    -24 - 5y = -9
    -5y = 15
    y = -3

  • algebra -

    ty

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