I was curious to know the analysis of a $4$ equation with $4$ unknowns. I know bunch of solutions like substitution, Cramer, etc. for solving this problem but couldn't find any analysis on this form.
For example I know three assumptions for a $2$ equations with $2$ unknowns:
- two lines may cross ($1$ answer - which is point),
- two lines may overlap (unlimited answers),
- two lines incoherent (no answers).
Is there any graphical analysis for a $4\times 4$ equation? Or an analysis which could explain the behavior of it?
Thanks in advance.