Here are some other examples of LaTeX expressions that can be built-up into a professional format. LaTeX assumes that each equation consists of two parts separated by a. The overbrace command places a brace.
If you want to close the bracket it is probably no case distinction and you shouldnt use the cases environment.
Label eqMaxwell which will reference the main equation 11 above or adding a label at the end of each line before the command which will reference the sub-equation 11a or 11b above. Braces bars and arrows. But I wonder whether one can obtain this result. Adding a label after the begin subequations command viz.