$$ax+b=c$$
$\left\{\begin{matrix}a=-\frac{b-c}{x}\text{, }&x\neq 0\\a\in \mathrm{C}\text{, }&b=c\text{ and }x=0\end{matrix}\right.$
$\left\{\begin{matrix}a=-\frac{b-c}{x}\text{, }&x\neq 0\\a\in \mathrm{R}\text{, }&b=c\text{ and }x=0\end{matrix}\right.$
$b=c-ax$
