let's solve for x :
- [tex] {x}^{2} + 6x - 4 = 3x + 6[/tex]
- [tex] {x}^{2} + 6x - 3x - 4 - 6 = 0[/tex]
- [tex] {x}^{2} + 3x - 10 = 0[/tex]
- [tex]x {}^{2} + 5x - 2x - 10=0[/tex]
- [tex]x(x + 5) - 2(x + 5)=0[/tex]
- [tex](x + 5)(x - 2)=0[/tex]
hence, the two roots of the above polynomial are -5 and 2