Question 212539
Using the addition method, what is the solution to 
2x-5y=4  
7x-2y=4 
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Multiply thru the 1st equation by 2; Multiply thru the 2nd equation by 5.
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4x-10y = 8
35x-10y = 20
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Subtract the 1st from the 2nd to solve for "x":
31x = 12
x = 12/31
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Substitute into 2x-5y=4 to solve for "y":
2(12/31) - 5y = 4
24/31 - 5y = 124/31
5y = -100/31
y = -20/31
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Cheers,
Stan H.