The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 16.1231\\[1 em]x_2 &= -8.3731 \end{aligned} $$The solutions of $ 4x^2-31x-540 = 0 $ are: $ x = \dfrac{ 31 }{ 8 }-\dfrac{\sqrt{ 9601 }}{ 8 } ~ \text{and} ~ x = \dfrac{ 31 }{ 8 }+\dfrac{\sqrt{ 9601 }}{ 8 }$.
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