The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 11.0492\\[1 em]x_2 &= -0.0246+0.7365i\\[1 em]x_3 &= -0.0246-0.7365i \end{aligned} $$Polynomial $ x^3-11x^2-6 $ has no rational roots that can be found using Rational Root Test, so the roots were found using qubic formulas.