The roots of polynomial $ p(z) $ are:
$$ \begin{aligned}z_1 &= -1+2i\\[1 em]z_2 &= -1-2i \end{aligned} $$The solutions of $ z^2+2z+5 = 0 $ are: $ z = -1+2i ~ \text{and} ~ z = -1-2i$.
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