The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 5.0748\\[1 em]x_2 &= -0.0374+1.1739i\\[1 em]x_3 &= -0.0374-1.1739i \end{aligned} $$Polynomial $ x^3-5x^2+x-7 $ has no rational roots that can be found using Rational Root Test, so the roots were found using qubic formulas.