SOLUTION: what is the solution of 1/x+2/y=9;7/x+11/y=54?

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Question 177697: what is the solution of 1/x+2/y=9;7/x+11/y=54?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
1%2Fx + 2%2Fy = 9
7%2Fx + 11%2Fy = 54
:
multiply both equations by xy, results:
y + 2x = 9xy
7y + 11x = 54xy
:
multiply the 1st equation by 7, subtract the 2nd equation from it
7y + 14x = 63xy
7y + 11x = 54xy
------------------
0 + 3x = 9xy
Divide both sides by 3x:
1 = 3y
y = 1%2F3
:
find x
y + 2x = 9xy
1%2F3 + 2x = 1%2F3*9x
1%2F3 + 2x = 3x
1%2F3 = 3x - 2x
x = 1%2F3
:
:
check solution
7%2Fx + 11%2Fy = 54
substitute 1/3 for x and y
(3*7) + (3*11) = 54