The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 1+\dfrac{\sqrt{ 15 }}{ 5 }i\\[1 em]x_2 &= 1- \dfrac{\sqrt{ 15 }}{ 5 }i \end{aligned} $$The solutions of $ -5x^2+10x-8 = 0 $ are: $ x = 1+\dfrac{\sqrt{ 15 }}{ 5 }i ~ \text{and} ~ x = 1-\dfrac{\sqrt{ 15 }}{ 5 }i$.
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