TeX source:
\begin{array}{rclcl} 0 &=& x^2-2x-48 &\vert& \text{p-q-Formel} \cr x_{2,3} &=& 1\pm\sqrt{1^2+48} \cr x_{2,3} &=& 1\pm\sqrt{49} \cr\cr x_2 &=& 1+7 = 8 \cr x_3 &=& 1-7 = -6 \cr\cr\mathbb{L} &=& \left\{-6;-1;8\right\}\end{array}