TeX Quellcode:

\begin{array}{rclcl} \dfrac{1}{4}x^2-x-3 &=& 0 & \vert & \cdot 4 \cr\cr x^2-4x-12 &=& 0 \cr x_{1,2} &=& 2\pm\sqrt{4+12} \cr x_{1,2} &=& 2\pm\sqrt{16} \cr \cr x_1 &=& 2+4 \; = \; 6 \cr x_2 &=& 2-4 \; = \; -2 \end{array}