Question 701995
What does the x represent in this situation 
3x = -4y-21 
5x+7y =39
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Rearrange:
3x + 4y = -21
5x + 7y = 39
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Multiply thru top by 7 and bottom by 4:
21x + 28y = -147
20x + 28y = 156
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Subtract and solve for "x":
x = -303
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Cheers,
Stan H.
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