The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= \dfrac{ 7 }{ 5 }\\[1 em]x_2 &= \dfrac{ 2 }{ 5 } \end{aligned} $$Step 1:
Get rid of fractions by multipling equation by $ \color{blue}{ 100 } $.
$$ \begin{aligned} x^2-\frac{18}{10}x+\frac{56}{100} & = 0 ~~~ / \cdot \color{blue}{ 100 } \\[1 em] 100x^2-180x+56 & = 0 \end{aligned} $$Step 2:
The solutions of $ 100x^2-180x+56 = 0 $ are: $ x = \dfrac{ 2 }{ 5 } ~ \text{and} ~ x = \dfrac{ 7 }{ 5 }$.
You can use step-by-step quadratic equation solver to see a detailed explanation on how to solve this quadratic equation.