The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -3.6754\\[1 em]x_2 &= -16.3246 \end{aligned} $$The solutions of $ x^2+20x+60 = 0 $ are: $ x = -10-2 \sqrt{ 10 } ~ \text{and} ~ x = -10+2 \sqrt{ 10 }$.
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