TeX Quellcode:

\begin{array}{crclllcc} \text{I} & 3x+4y &=& -6 & \vert \cdot 5 \cr \text{II} & -5x-2y &=& -4 & \vert \cdot 3 \cr \cr \text{I} & 15x+20y &=& -30 \cr \text{II} & -15x-6y &=& -12 \cr \cr \text{I} & 15x+20y &=& -30 \cr \text{I+II} & 0x +14y &=& -42 & \Rightarrow y = -3 \cr \cr y=-3 \text{ in I} & 3x+4 \cdot (-3) &=& -6 &\vert +12 \cr & 3x &=& 6 & \Rightarrow x = 2 \cr \cr & \mathbb{L} &=& \{\left(2; -3\right)\} \end{array}