3. (30 pts) (Problem 9.12): Given the system of equations 2x x2-x3-1 5x1 +2x2 + 2x34 3x1 + x2 +x3 5 a) Use graphical method to estimate the solution: b) Write a MATLAB function using Gauss-Jordan elimination to solve for xi, X2, and x3; c) Check your answer using the check' function you wrote in problem 2.e to verify the solution; d) If equation (1) and (2) remain the same, but equation (3) is changed to 2.5x1 x2 x35, write the equations into the format of Ax - b, calculate the determinant of matrix A using the function you wrote in problem 1.c, and discuss the solution of the new system of equations. 3. (30 pts) (Problem 9.12): Given the system of equations 2x x2-x3-1 5x1 +2x2 + 2x34 3x1 + x2 +x3 5 a) Use graphical method to estimate the solution: b) Write a MATLAB function using Gauss-Jordan elimination to solve for xi, X2, and x3; c) Check your answer using the check' function you wrote in problem 2.e to verify the solution; d) If equation (1) and (2) remain the same, but equation (3) is changed to 2.5x1 x2 x35, write the equations into the format of Ax - b, calculate the determinant of matrix A using the function you wrote in problem 1.c, and discuss the solution of the new system of equations