Question

I have a Kumon math question. can someone help me?

Answer 1

$\begin{gathered} x^2-2x-8=0 \\ x=\frac{2\pm\sqrt[]{4+32}}{2} \\ x=\frac{2\pm\sqrt[]{36}}{2} \\ x=\frac{2\pm6}{2} \\ x=4,-2 \end{gathered}$