The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= \frac{ 9 }{ 10 }+\frac{\sqrt{ 269 }}{ 10 }i\\[1 em]x_2 &= \frac{ 9 }{ 10 }- \frac{\sqrt{ 269 }}{ 10 }i \end{aligned} $$Step 1:
Get rid of fractions by multipling equation by $ \color{blue}{ 10 } $.
$$ \begin{aligned} x^2-\frac{18}{10}x+\frac{35}{10} & = 0 ~~~ / \cdot \color{blue}{ 10 } \\[1 em] 10x^2-18x+35 & = 0 \end{aligned} $$Step 2:
The solutions of $ 10x^2-18x+35 = 0 $ are: $ x = \dfrac{ 9 }{ 10 }+\dfrac{\sqrt{ 269 }}{ 10 }i ~ \text{and} ~ x = \dfrac{ 9 }{ 10 }-\dfrac{\sqrt{ 269 }}{ 10 }i$.
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