2 x + 4*x - 7
x^2 + 4*x - 7
2 -7 + x + 4*x
-7 + x^2 + 4*x
/ ____\ / ____\ \x + 2 - \/ 11 /*\x + 2 + \/ 11 /
(x + 2 - sqrt(11))*(x + 2 + sqrt(11))
-7.0 + x^2 + 4.0*x
-7 + x*(4 + x)