The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 1.0964\\[1 em]x_2 &= -1.0964\\[1 em]x_3 &= -4.5605\\[1 em]x_4 &= 4.5605 \end{aligned} $$Polynomial $ x^4-22x^2+25 $ has no rational roots that can be found using Rational Root Test, so the roots were found using quartic formulas.