TeX Quellcode:

\begin{array}{rclll}\dfrac{4x}{-4x-72} &=& \dfrac{9}{2x+3}&\vert & \cdot\left(-4x-72\right)\left(2x+3\right) \cr\cr4x\cdot\left(2x+3\right) &=& 9\cdot\left(-4x-72\right) \cr8x^2+12x &=& -36x-648 &\vert &+36x+648 \cr8x^2+48x+648 &=& 0 &\vert & : 8 \cr x^2+6x+81 &=& 0 &\vert& \text{p-q-Formel} \cr x_{1,2} &=& -3\pm\sqrt{3^2-81} \cr x_{1,2} &=& -3\pm\sqrt{-72} \end{array}