The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 68.0789\\[1 em]x_2 &= -8.0789 \end{aligned} $$The solutions of $ x^2-60x-550 = 0 $ are: $ x = 30-5 \sqrt{ 58 } ~ \text{and} ~ x = 30+5 \sqrt{ 58 }$.
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