Solve Systems of Linear Equations: This contains everything needed to teach solving systems of linear equations. Contains step-by-step instructions for solving by graphing, solving using substitution, & solving using the elimination / combination method. This lesson will take about 3 to 4 days to teach. The 30-slide PowerPoint lesson goes in depth into what constitutes a system of linear equations as well as how to solve them by graphing, using the substitution method, and the elimination (o