The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 5.6056\\[1 em]x_2 &= -1.6056 \end{aligned} $$The solutions of $ x^2-4x-9 = 0 $ are: $ x = 2-\sqrt{ 13 } ~ \text{and} ~ x = 2+\sqrt{ 13 }$.
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