2 5*x - 4*x + 7
5*x^2 - 4*x + 7
2 7 - 4*x + 5*x
7 - 4*x + 5*x^2
/ ____\ / ____\ | 2 I*\/ 31 | | 2 I*\/ 31 | |x + - - + --------|*|x + - - - --------| \ 5 5 / \ 5 5 /
(x - 2/5 + i*sqrt(31)/5)*(x - 2/5 - i*sqrt(31)/5)
7.0 + 5.0*x^2 - 4.0*x
7 + x*(-4 + 5*x)