SOLUTION: x=5-9y 4x+9y=-7

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Question 1104044: x=5-9y
4x+9y=-7
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
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x=5-9y
4x+9y=-7
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4%285-9y%29%2B9y=-7
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Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
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The given system is equivalent to THIS

 x + 9y =  5,    (1)
4x + 9y = -7,    (2)


Subtract eq(1) from eq(2) (both sides). You will get

4x - x = -7 - 5,   or

3x = - 12  ====>  x = -12%2F3 = -4.


Then from eq(1) 9y = 5 - x = 5 - (-4) = 9  ====>  y = 1.


Answer.  The solution is  (x,y) = (-4,1).