The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.2219\\[1 em]x_2 &= -0.2698 \end{aligned} $$The solutions of $ 835x^2+40x-50 = 0 $ are: $ x = -\dfrac{ 4 }{ 167 }-\dfrac{\sqrt{ 1686 }}{ 167 } ~ \text{and} ~ x = -\dfrac{ 4 }{ 167 }+\dfrac{\sqrt{ 1686 }}{ 167 }$.
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