TeX Quellcode:

\begin{array}{rclcc} a^2+b^2 &=& c^2 & \vert & \sqrt{} \cr c &=& \sqrt{a^2+b^2} \cr &=& \sqrt{3^2+4^2} \cr &=& \sqrt{25} \cr &=& 5 \, cm \end{array}