The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 1\\[1 em]x_2 &= -\frac{ 2 }{ 3 } \end{aligned} $$Step 1:
Combine like terms:
$$ \color{blue}{x^2} + \color{blue}{2x^2} -x-2 = \color{blue}{3x^2} -x-2 $$Step 2:
The solutions of $ 3x^2-x-2 = 0 $ are: $ x = -\dfrac{ 2 }{ 3 } ~ \text{and} ~ x = 1$.
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