SOLUTION: {{{x-y=7}}}; {{{2/x-5/y=2}}} solution

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Question 769989: x-y=7; 2%2Fx-5%2Fy=2 solution
Answer by Jc0110(165) About Me  (Show Source):
You can put this solution on YOUR website!
x-y=7
x=y%2B7 --> Equation 1 ... Substitute x=y%2B7 into Equation 2
2%2Fx-5%2Fy=2
xy%282%2Fx%29-xy%285%2Fy%29=xy%282%29
2y-5x=2xy --> Equation 2
2y-5%28y%2B7%29=2y%28y%2B7%29
2y-5y-35=2y%5E2%2B14y
-3y-35=2y%5E2%2B14y
0=2y%5E2%2B14y%2B3y%2B35
0=2y%5E2%2B17y%2B35
2y%5E2%2B17y%2B35=0
%282y%2B7%29%28y%2B5%29=0
y=-7%2F2 or y=-5
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When y=-7%2F2, --> Substitute y=-7%2F2 into x=y%2B7
x=-7%2F2%2B7
x=7%2F2
x=3%261%2F2
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When y=-5, --> Substitute y=-5 into x=y%2B7
x=-5%2B7
x=2
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Therefore,
when x=3%261%2F2, y=-7%2F2;
when x=2, y=-5.