Sassini is right but it is not finished
$${\mathtt{9}}{\mathtt{\,-\,}}{\mathtt{12}}{i}{\mathtt{\,\small\textbf+\,}}{\mathtt{4}}\left[{{i}}^{{\mathtt{2}}}\right]$$
= $${\mathtt{9}}{\mathtt{\,-\,}}{\mathtt{12}}{i}{\mathtt{\,-\,}}{\mathtt{4}}$$
= $${\mathtt{5}}{\mathtt{\,-\,}}{\mathtt{12}}{i}$$
$${\left({\mathtt{3}}{\mathtt{\,-\,}}{\mathtt{2}}{i}\right)}^{{\mathtt{2}}}$$
$${\mathtt{9}}{\mathtt{\,-\,}}{\mathtt{12}}{i}{\mathtt{\,\small\textbf+\,}}{\mathtt{4}}\left[{{i}}^{{\mathtt{2}}}\right]$$
.Sassini is right but it is not finished
$${\mathtt{9}}{\mathtt{\,-\,}}{\mathtt{12}}{i}{\mathtt{\,\small\textbf+\,}}{\mathtt{4}}\left[{{i}}^{{\mathtt{2}}}\right]$$
= $${\mathtt{9}}{\mathtt{\,-\,}}{\mathtt{12}}{i}{\mathtt{\,-\,}}{\mathtt{4}}$$
= $${\mathtt{5}}{\mathtt{\,-\,}}{\mathtt{12}}{i}$$