TeX Quellcode:

\begin{array}{rclcll}\dfrac{20}{-y+13} &\leq & 15 &\vert & \cdot\left(-y+13\right)\\20 &\geq & 15\left(-y+13\right)\\20 &\geq & -15y+195 &\vert & -195\\-175 &\geq & -15y &\vert & :\left(-15\right)\\\dfrac{35}{3} &\leq & y\end{array}