X(x(x-1))+6=x(x+3)(x-4)
X(x^2 - x) + 6 = x( x^2 - x - 12) x^3 - x^2 + 6 = x^3 - x^2 - 12x x^3 - x^3 - x^2 + x^2 + 12x = - 6 12x = - 6 x = - 6/12 x = - 0,5