a)[tex]3 x^{2} -4x-4=0 [/tex] a=3 b=-4 c=-4 Δ =b²-4ac Δ=16+48 =64 x1 = [tex] \frac{4+8}{6 } = \frac{12}{6} = 2 [/tex] x2= [tex] \frac{4-8}{6} = \frac{-4}{6} = \frac{-2}{3} [/tex] b)5x²+3x=0 Δ=b²-4ac Δ = 9-0 = 9 x1= [tex] \frac{-3+3}{10} = 0 [/tex] si x2= [tex] \frac{-3-3}{10} = \frac{-6}{10 } = \frac{-3}{5} [/tex] c) x²-x-2 =0 Δ=b²-4ac Δ = 1+8 = 9 x1 =[tex] \frac{1+3}{2} = \frac{4}{2} =2 [/tex] si x2 = [tex] \frac{1-3}{2} = \frac{-2}{2} = -1[/tex]