The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 1.6589\\[1 em]x_2 &= -1.8341\\[1 em]x_3 &= 11.1752 \end{aligned} $$Step 1:
Combine like terms:
$$ \color{blue}{4} +x^3-11x^2-5x+ \color{blue}{30} = x^3-11x^2-5x+ \color{blue}{34} $$Step 2:
Polynomial $ x^3-11x^2-5x+34 $ has no rational roots that can be found using Rational Root Test, so the roots were found using qubic formulas.