The roots of polynomial $ p(a) $ are:
$$ \begin{aligned}a_1 &= 6.7417\\[1 em]a_2 &= -0.7417 \end{aligned} $$The solutions of $ a^2-6a-5 = 0 $ are: $ a = 3-\sqrt{ 14 } ~ \text{and} ~ a = 3+\sqrt{ 14 }$.
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