The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -\frac{ 8 }{ 3 }+\frac{\sqrt{ 26 }}{ 3 }i\\[1 em]x_2 &= -\frac{ 8 }{ 3 }- \frac{\sqrt{ 26 }}{ 3 }i \end{aligned} $$The solutions of $ 3x^2+16x+30 = 0 $ are: $ x = -\dfrac{ 8 }{ 3 }+\dfrac{\sqrt{ 26 }}{ 3 }i ~ \text{and} ~ x = -\dfrac{ 8 }{ 3 }-\dfrac{\sqrt{ 26 }}{ 3 }i$.
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