Question

3x x - 4
--- - -------
x - 1 x^2 - 2x + 1

Answer 1

x^2-2x+1 can be factored into (x-1)^2 so just multiply 3x/(x-1) by (x-1)/(x-1) to get a common denominator

Answer 2

your new expression should look like this
3x(x-1)-(x-4)/(x-1)^2=3x^2-3x-x+4/(x-1)^2
=3x^2-4x+4/(x-1)^2