The roots of polynomial $ p(p) $ are:
$$ \begin{aligned}p_1 &= 15.8452\\[1 em]p_2 &= -9.8452 \end{aligned} $$The solutions of $ p^2-6p-156 = 0 $ are: $ p = 3-\sqrt{ 165 } ~ \text{and} ~ p = 3+\sqrt{ 165 }$.
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