The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.1513\\[1 em]x_2 &= -0.7346 \end{aligned} $$The solutions of $ 72x^2+42x-8 = 0 $ are: $ x = -\dfrac{ 7 }{ 24 }-\dfrac{\sqrt{ 113 }}{ 24 } ~ \text{and} ~ x = -\dfrac{ 7 }{ 24 }+\dfrac{\sqrt{ 113 }}{ 24 }$.
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