The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -14.694\\[1 em]x_2 &= 1.347+0.8784i\\[1 em]x_3 &= 1.347-0.8784i \end{aligned} $$Polynomial $ x^3+12x^2-37x+38 $ has no rational roots that can be found using Rational Root Test, so the roots were found using qubic formulas.