The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -13.5425\\[1 em]x_2 &= -66.4575 \end{aligned} $$The solutions of $ x^2+80x+900 = 0 $ are: $ x = -40-10 \sqrt{ 7 } ~ \text{and} ~ x = -40+10 \sqrt{ 7 }$.
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