TeX Quellcode:

\begin{array}{crclllcc} \text{I} & 4a+12y &=& -8 & \vert & -12y \cr & 4a &=& -8-12y & \vert & :4 \cr & a &=& -2-3y \cr \cr & \mathbb{L} &=& \{\left(-2-3y; y\right) \text{ mit }y \in \mathbb{R}\} \end{array}