The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.5611\\[1 em]x_2 &= 3.2195+3.32i\\[1 em]x_3 &= 3.2195-3.32i \end{aligned} $$Polynomial $ x^3-7x^2+25x-12 $ has no rational roots that can be found using Rational Root Test, so the roots were found using qubic formulas.