a) Use the inverse matrix method to solve the following system of equations (note: use the Gauss-Jordan elimination method to determine the required inverse matrix. Be sure to show your workings. If any other method, other than the Gauss-Jordan, is used or your workings not shown, you will be awarded a zero mark). 3x + 2y - z =9 2z - x +4y = 5 -2y+x+ z = 3 2 b) Let matrix A = 2 2 If |A| = 0, find x -1 (x - 4) (5 + 3 = 8 marks)