$\left\{\begin{array}{l} x+y=100\\ y-7=\dfrac{40}{100(x-33)}(x\ne 33)\end{array} \right.\\ \Leftrightarrow \left\{\begin{array}{l} x=100-y\\ y-7=\dfrac{40}{100(100-y-33)}\end{array} \right.\\ \Leftrightarrow \left\{\begin{array}{l} x=100-y\\ (y-7)100(100-y-33)=40\end{array} \right.\\ \Leftrightarrow \left\{\begin{array}{l} x=100-y\\ -100y^2+7400y-46940=0\end{array} \right.\\ \Leftrightarrow \left[\begin{array}{l} y=\dfrac{185+\sqrt{22490}}{5};x=\dfrac{315+\sqrt{22490}}{5}\\ y=\dfrac{185-\sqrt{22490}}{5};x=\dfrac{315-\sqrt{22490}}{5}\end{array} \right.$