The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 2+3i\\[1 em]x_2 &= 2-3i \end{aligned} $$The solutions of $ x^2-4x+13 = 0 $ are: $ x = 2+3i ~ \text{and} ~ x = 2-3i$.
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