The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 3.3094\\[1 em]x_2 &= -4.1094 \end{aligned} $$The solutions of $ -5x^2-4x+68 = 0 $ are: $ x = -\dfrac{ 2 }{ 5 }-\dfrac{ 2 \sqrt{ 86}}{ 5 } ~ \text{and} ~ x = -\dfrac{ 2 }{ 5 }+\dfrac{ 2 \sqrt{ 86}}{ 5 }$.
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