SOLUTION: Please help solve the equation and give the x-value solution 1/2x+3/5y=3/2 -1/4x-1/8y=1/8

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Question 64680: Please help solve the equation and give the x-value solution
1/2x+3/5y=3/2
-1/4x-1/8y=1/8
Answer by chitra(359) About Me  (Show Source):
You can put this solution on YOUR website!
The given equations are:

%281%2F2%29x+%2B+%283%2F5%29y+=+%283%2F2%29 -------------> (1)


%28-1%2F4%29x+-+%281%2F8%29y+=+%281%2F8%29 -------------> (2)


Multiply EQN (1) by %281%2F2%29, we get:



%281%2F4%29x+%2B+%283%2F10%29y+=+%283%2F4%29 -------------> (3)



Adding (2) and (3), we get:


%287%2F40%29y+=+%287%2F8%29


Hence, y = %287%2F8%29+%2A+%2840%2F7%29


This implies, y = 5


Now, substituting for y in any of the above equations, either in (1) or (2) we get the value of x.


So substituting for y in (1), we get:


%281%2F2%29x+%2B+%283%2F5%29%2A5+=+%283%2F2%29


%281%2F2%29x+%2B+3+=+%283%2F2%29


%281%2F2%29x+=+%283%2F2%29+-+3


%281%2F2%29x+=+-%283%2F2%29


This implies,

x = -%283%2F2%29+%2A+%282%2F1%29

x = -3


Hence, the solution.