The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -\dfrac{ 9 }{ 16 }\\[1 em]x_2 &= -4 \end{aligned} $$The solutions of $ 16x^2+73x+36 = 0 $ are: $ x = -4 ~ \text{and} ~ x = -\dfrac{ 9 }{ 16 }$.
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