The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.8468\\[1 em]x_2 &= -2.0468 \end{aligned} $$The solutions of $ 15x^2+18x-26 = 0 $ are: $ x = -\dfrac{ 3 }{ 5 }-\dfrac{\sqrt{ 471 }}{ 15 } ~ \text{and} ~ x = -\dfrac{ 3 }{ 5 }+\dfrac{\sqrt{ 471 }}{ 15 }$.
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