The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -3+3i\\[1 em]x_2 &= -3-3i \end{aligned} $$The solutions of $ x^2+6x+18 = 0 $ are: $ x = -3+3i ~ \text{and} ~ x = -3-3i$.
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