The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.7255\\[1 em]x_2 &= -1.2494\\[1 em]x_3 &= 1.3239 \end{aligned} $$Step 1:
Write polynomial in descending order
$$ \begin{aligned} 8x-6+4x^2-5x^3 & = 0\\[1 em] -5x^3+4x^2+8x-6 & = 0 \end{aligned} $$Step 2:
Polynomial $ -5x^3+4x^2+8x-6 $ has no rational roots that can be found using Rational Root Test, so the roots were found using qubic formulas.