The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.1086\\[1 em]x_2 &= -0.1919 \end{aligned} $$Step 1:
Get rid of fractions by multipling equation by $ \color{blue}{ 4 } $.
$$ \begin{aligned} 12x^2+x-\frac{1}{4} & = 0 ~~~ / \cdot \color{blue}{ 4 } \\[1 em] 48x^2+4x-1 & = 0 \end{aligned} $$Step 2:
The solutions of $ 48x^2+4x-1 = 0 $ are: $ x = -\dfrac{ 1 }{ 24 }-\dfrac{\sqrt{ 13 }}{ 24 } ~ \text{and} ~ x = -\dfrac{ 1 }{ 24 }+\dfrac{\sqrt{ 13 }}{ 24 }$.
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