The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 30.3297\\[1 em]x_2 &= -0.3297 \end{aligned} $$The solutions of $ -x^2+30x+10 = 0 $ are: $ x = 15-\sqrt{ 235 } ~ \text{and} ~ x = 15+\sqrt{ 235 }$.
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