The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.9059\\[1 em]x_2 &= -1.6559 \end{aligned} $$Step 1:
Get rid of fractions by multipling equation by $ \color{blue}{ 2 } $.
$$ \begin{aligned} -2x^2-\frac{3}{2}x+3 & = 0 ~~~ / \cdot \color{blue}{ 2 } \\[1 em] -4x^2-3x+6 & = 0 \end{aligned} $$Step 2:
The solutions of $ -4x^2-3x+6 = 0 $ are: $ x = -\dfrac{ 3 }{ 8 }-\dfrac{\sqrt{ 105 }}{ 8 } ~ \text{and} ~ x = -\dfrac{ 3 }{ 8 }+\dfrac{\sqrt{ 105 }}{ 8 }$.
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