The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -5.5462\\[1 em]x_2 &= -0.9769+1.0997i\\[1 em]x_3 &= -0.9769-1.0997i \end{aligned} $$Polynomial $ 2x^3+15x^2+26x+24 $ has no rational roots that can be found using Rational Root Test, so the roots were found using qubic formulas.