Question 303946
z^2 - 2z + 1 factors to (z-1)(z-1)


4z^2 - z - 3 factors to (4z+3)(z-1)


[(z-1)(z-1)] / [(4z+3)(z-1)]


one of the (z-1) in the numerator cancels with the (z-1) in the denominator


leaving ___ (z-1) / (4z+3)