The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 10+5 \sqrt{ 26 }i\\[1 em]x_2 &= 10-5 \sqrt{ 26 }i \end{aligned} $$The solutions of $ x^2-20x+750 = 0 $ are: $ x = 10+5 \sqrt{ 26 }i ~ \text{and} ~ x = 10-5 \sqrt{ 26 }i$.
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