Determine equations of all lines

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Homework Statement



Determine equations of all lines the are tangent to y=x^2/(x-1) and that pass through the point (2,0).

Homework Equations





The Attempt at a Solution


First I found the y' which I came up with y'=x(x-2)/(x-1)^2

next, let (a,f(a)) and put a to y'
f'(a)=a(a-2)/(a-1)^2 (slope of tangent lines at x=a) ->①
also this slope is given by f(a)-0/a-2 -> ②
①=② then solve for a, but I stuck for calculating this...

Am I on the right truck ?? can anyone help me, please??
 
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You have the x,y co-ordinates of a general point on the curve, you have the slope of the tangent through that point, get the equation for that line. When you have done that I expect you can do the rest too.
 
What is the slope of a line passing through points (x1, y1) and (x2, y2) ?

Then:
Let (x2, y2) = (a, f(a)), and (x1, y1) = (2, 0). You know the slope of the line passing through these two points must be f ' (a) , if the line is to be tangent to the curve y=x2/(x-1) at x = a.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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