1 1 1 3. Let A: 4 5 [I [I 1 3 (a) (8 pts) Use elementary mu: operations to nd A'l. Other methods receive NO credit. Show each step of your work and indicate each ERO used. (b) (2 pts) Use the method of matrix inverse and the result in (a) to solve the following system of equations. Other methods may receive NO credit. :I:yz=1 4I+By =0 ySz=2