TeX Quellcode:

\begin{array}{crcrcrcl} \text{II'} & 11y &-& 20z &=& -13 & \vert & +20z \cr & 11y & & &=& -13+20z & \vert & :11 \cr\cr&&& y &=& -\dfrac{13}{11}+\dfrac{20}{11}z \end{array}