The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -2.1544\\[1 em]x_2 &= 1.0772+1.8658i\\[1 em]x_3 &= 1.0772-1.8658i \end{aligned} $$Polynomial $ x^3+10 $ has no rational roots that can be found using Rational Root Test, so the roots were found using qubic formulas.