Question 308280
[ (x^2 + 3x + 9) / (x^2 – 9) ][ (x + 3) / (x^3 - 27) ]

(x^2 + 3x + 9)/(x+3)(x-3) * (x+3)(x-a)/(x^2+3x+9)

x-3 / x-a