The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 2.4853\\[1 em]x_2 &= -14.4853 \end{aligned} $$The solutions of $ x^2+12x-36 = 0 $ are: $ x = -6-6 \sqrt{ 2 } ~ \text{and} ~ x = -6+6 \sqrt{ 2 }$.
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