The roots of polynomial $ p(s) $ are:
$$ \begin{aligned}s_1 &= 10+10i\\[1 em]s_2 &= 10-10i \end{aligned} $$The solutions of $ s^2-20s+200 = 0 $ are: $ s = 10+10i ~ \text{and} ~ s = 10-10i$.
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