The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -8+5i\\[1 em]x_2 &= -8-5i \end{aligned} $$The solutions of $ x^2+16x+89 = 0 $ are: $ x = -8+5i ~ \text{and} ~ x = -8-5i$.
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