2х^2 +11x+34=(x+6)^2
2x²+11x+34=(x+6)² 2x²+11x+34=x²+12x+36 2x²-x²+11x-12x+34-36=0 x²-x-2=0 D=1+8=9=3² x₁=(1-3)/2=-2/2=-1 x₂=(1+3)/2=4/2=2