$\left\{\begin{matrix}n=-\frac{ia}{4stu}\text{, }&s\neq 0\text{ and }t\neq 0\text{ and }u\neq 0\\n\in \mathrm{C}\text{, }&\left(u=0\text{ or }t=0\text{ or }s=0\right)\text{ and }a=0\end{matrix}\right.$
Steps for Solving Linear Equation
Multiply $4$ and $i$ to get $4i$.
$$a=4iunts$$
Swap sides so that all variable terms are on the left hand side.
$$4iunts=a$$
The equation is in standard form.
$$4istun=a$$
Divide both sides by $4iuts$.
$$\frac{4istun}{4istu}=\frac{a}{4istu}$$
Dividing by $4iuts$ undoes the multiplication by $4iuts$.
