SOLUTION: 3/7x+5/9y=27 and 1/9x+2/7y=7

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Question 257488: 3/7x+5/9y=27 and 1/9x+2/7y=7
Found 2 solutions by drk, stanbon:
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
The two equations are:
(i) %283%2F7%29x%2B%285%2F9%29y=27
(ii) %281%2F9%29x%2B%282%2F7%29y=7
multiply both equations by 63 to get
(iii) %2827%29x%2B%2835%29y=1701
(iv) %287%29x%2B%2818%29y=441
multiply (iii) by 7 and (iv) by -27 to get
(v) %28189%29x%2B%28245%29y=11907
(vi) %28-189%29x%2B%28-486%29y=-11907
adding down, we get
-241y+=+0
y = 0.
x = 63
{63,0)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
(3/7)x+(5/9)y=27
(1/9)x+(2/7)y=7
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Multiply thru the 1st by 63 and the 2nd by 63 to get:
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9*3x + 7*5y = 63*27
7*x + 9*2y = 63*7
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27x + 35y = 63*27
7x + 18y = 63*7
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Multiply the 1st by 7 and the 2nd by 27 to get:
7*27x + 7*35y = 7*63*27
27*7x + 27*18y = 27*63*7
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Subtract the 1st from the 2nd and solve for "y":
45y = 0
y = 0
------
Substitute into 7x + 18y = 7*63 to solve for "x":
7x = 7*63-0
x = 63
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Cheers,
Stan H.