The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -\frac{ 7 }{ 3 }\\[1 em]x_2 &= -6 \end{aligned} $$The solutions of $ 3x^2+25x+42 = 0 $ are: $ x = -6 ~ \text{and} ~ x = -\dfrac{ 7 }{ 3 }$.
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