The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= \frac{ 28 }{ 5 }+\frac{ 4 }{ 5 }i\\[1 em]x_2 &= \frac{ 28 }{ 5 }-\frac{ 4 }{ 5 }i \end{aligned} $$The solutions of $ 5x^2-56x+160 = 0 $ are: $ x = \dfrac{ 28 }{ 5 }+\dfrac{ 4 }{ 5 }i ~ \text{and} ~ x = \dfrac{ 28 }{ 5 }-\dfrac{ 4 }{ 5 }i$.
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