help .. 分式方程組 x5

As follows:


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1/(x+y)+1/y=2-----------------1
{
1/(x+y)-1/y=0------------------2

1-2,
1/(x+y)-1/(x+y)+1/y-(-1/y)=2-0
2/y=2
2=2y
y=1
sub.y=1 into 1
1/(x+1)+1/1=2
1/(x+1)=1
1=x+1
x=0