$\left\{\begin{matrix}c=\frac{400gk}{9m}-\frac{65}{9}\text{, }&m\neq 0\\c\in \mathrm{R}\text{, }&\left(k=0\text{ or }g=0\right)\text{ and }m=0\end{matrix}\right.$

$\left\{\begin{matrix}g=\frac{m\left(9c+65\right)}{400k}\text{, }&k\neq 0\\g\in \mathrm{R}\text{, }&\left(m=0\text{ or }c=-\frac{65}{9}\right)\text{ and }k=0\end{matrix}\right.$