The roots of polynomial $ p(m) $ are:
$$ \begin{aligned}m_1 &= \frac{ 1 }{ 7 }\\[1 em]m_2 &= -1 \end{aligned} $$The solutions of $ 7m^2+6m-1 = 0 $ are: $ m = -1 ~ \text{and} ~ m = \dfrac{ 1 }{ 7 }$.
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