The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -8+4i\\[1 em]x_2 &= -8-4i \end{aligned} $$The solutions of $ -6x^2-96x-480 = 0 $ are: $ x = -8+4i ~ \text{and} ~ x = -8-4i$.
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