The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 12\\[1 em]x_2 &= -5 \end{aligned} $$The solutions of $ x^2-7x-60 = 0 $ are: $ x = -5 ~ \text{and} ~ x = 12$.
You can use step-by-step quadratic equation solver to see a detailed explanation on how to solve this quadratic equation.