I'm stuck on the following problem:

"Find the equations of both lines through the point (1,2) that are tangent to the curve y=x/(x+1)"

So far, I have that y'=1/(x+1)^2. I tried setting that equal to the slope (2-(x/(x+1)))/(1-x) but it isn't working out. Not sure where to go from here, any help would be much appreciated