The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.3664\\[1 em]x_2 &= -4.3664 \end{aligned} $$The solutions of $ 5x^2+20x-8 = 0 $ are: $ x = -2-\dfrac{ 2 \sqrt{ 35}}{ 5 } ~ \text{and} ~ x = -2+\dfrac{ 2 \sqrt{ 35}}{ 5 }$.
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