Question

I have some essential questions that I'm not really sure how to put into words. I seem to understand the lessons but I have no idea how to answer these questions. Can anyone help me get on the right track? EQ: how do systems of non-linear equations represent "Real life" situations,What methods can be used to solve a system of equations?,
What type of solutions do the methods for solving systems of equations find?,ow can elimination and substitution adapt to solve a system with non-linear equations?,How can graphing methods be used to solve a system of linear equations?