The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -6+2 \sqrt{ 6 }i\\[1 em]x_2 &= -6-2 \sqrt{ 6 }i \end{aligned} $$The solutions of $ x^2+12x+60 = 0 $ are: $ x = -6+2 \sqrt{ 6 }i ~ \text{and} ~ x = -6-2 \sqrt{ 6 }i$.
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