The roots of polynomial $ p(m) $ are:
$$ \begin{aligned}m_1 &= -0.5464\\[1 em]m_2 &= -27.4536 \end{aligned} $$The solutions of $ m^2+28m+15 = 0 $ are: $ m = -14-\sqrt{ 181 } ~ \text{and} ~ m = -14+\sqrt{ 181 }$.
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