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Math Help - Would you check out my answer please?

  1. #1
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    Would you check out my answer please?

    I need to solve this equation couple.
    Is this correctly solved?
    Thanks!

    7x + 9y - 8 = 0
    9x - 8y - 69 = 0

    7x + 9y = 8
    9y = 8 - 7x

    8 * 9y = 8 * (8-7x)
    72y = 64 - 56x


    9x - 8y = 69
    -8y = 69 - 9x
    -9 * (-8y) = -9 * (69 - 9x)
    72y = 81x - 621

    64-56x = 81x - 621
    64 - 56x + 621 = 81x
    64 + 621 - 56x = 81x
    685 = 81x + 56x
    685 = 137x

    x = 685/137 = 5

    7 * (5) + 9y - 8 = 0
    35 + 9y - 8 = 0
    27 + 9y = 0
    9y = -27
    y = -3

    Solution:
    X=5
    Y=-3
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  2. #2
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    If your x and y values are correct, when you plug them into each equation, they should give you true statements, like 5 = 5.

    This style of problem is certainly checkable, plug in and see if you are right.
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  3. #3
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    Thanks, but I didn't mean the answer. Would someone check out if my solving method is correct or not? Please!
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  4. #4
    Like a stone-audioslave ADARSH's Avatar
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    Would someone check out if my solving method is correct or not? Please!
    Its correct
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