The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.2224\\[1 em]x_2 &= 0.5539\\[1 em]x_3 &= -4.8882+2.9278i\\[1 em]x_4 &= -4.8882-2.9278i \end{aligned} $$Polynomial $ x^4+9x^3+25x^2-24x+4 $ has no rational roots that can be found using Rational Root Test, so the roots were found using quartic formulas.