The roots of polynomial $ p(y) $ are:
$$ \begin{aligned}y_1 &= -1.5858\\[1 em]y_2 &= -4.4142 \end{aligned} $$The solutions of $ y^2+6y+7 = 0 $ are: $ y = -3-\sqrt{ 2 } ~ \text{and} ~ y = -3+\sqrt{ 2 }$.
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