2 5*x - 45
5*x^2 - 1*45
1*(x + 3)*(x - 3)
(1*(x + 3))*(x - 3)
-45.0 + 5.0*x^2
/ 2\ 5*\-9 + x /
5*(-9 + x^2)
5*(-3 + x)*(3 + x)