The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.5782\\[1 em]x_2 &= 3.0977\\[1 em]x_3 &= -0.238+0.7083i\\[1 em]x_4 &= -0.238-0.7083i \end{aligned} $$Polynomial $ 5x^4-16x^3+3x^2-6x+5 $ has no rational roots that can be found using Rational Root Test, so the roots were found using quartic formulas.