The roots of polynomial $ p(b) $ are:
$$ \begin{aligned}b_1 &= 0.899\\[1 em]b_2 &= -8.899 \end{aligned} $$The solutions of $ b^2+8b-8 = 0 $ are: $ b = -4-2 \sqrt{ 6 } ~ \text{and} ~ b = -4+2 \sqrt{ 6 }$.
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