2 x - 3*x - 4
x^2 - 3*x - 4
(x + 1)*(x - 4)
2 -4 + x - 3*x
-4 + x^2 - 3*x
(1 + x)*(-4 + x)
-4 + x*(-3 + x)
-4.0 + x^2 - 3.0*x