ABSTRACT
Gauss elimination, back substitution, free parameters, Type I, Type II, and Type III operations; pivot
This is a good time to go back to your linear algebra book and review the procedure of Gauss elimination with back substitution to obtain a solution to a system of linear equations. We will give only a brief refresher here. First, we recall how nice “upper triangular” systems are. Suppose we need to solve
2x1 + x2 − x3 = 5 x2 + x3 = 3
3x3 = 6 .
