This document summarizes the Gaussian elimination method for solving systems of linear equations. It discusses: 1) Gaussian elimination involves eliminating variables from equations to put the system in triangular form without or with pivoting. 2) When solving without pivoting, the process introduces zeros below the diagonal and results in A = LU decomposition, where L is lower triangular and U is upper triangular. 3) To solve for x, the system is decomposed into Ly = b and Ux = y and then solved step-by-step. 4) Pivoting may be used by permuting rows to choose optimal elements for elimination and ensures the method remains numerically stable.