4. Let A = X-1 -2 -1 X-3 -1 2 1 -4 X+2, (a) (4 points) For what values of A will the homogeneous system Ax = 0 have infinitely many solutions? Explain your answer. (b) (6 points) For each of the values of A found in (a), write down the general solution for the homogeneous system Ax = 0. Show your working clearly, however, you do not need to show the elementary row operations used.

Fig: 1