TeX Quellcode:
\begin{array}{rcl} 4x \cdot x-3x \cdot y+11x \cdot x+16x-40y+3y \cdot x &=& 4x \cdot x+11x \cdot x-3x \cdot y+3x \cdot y+16x-40y \cr &=& 15x \cdot x+16x-40y \end{array}