(a) 2X1 + X2 - X3 = 8
-3X1 - X2 + 2X3= -11
-2X1 + X2 + 2X3= -3
(b) 3X1 - X2 + 5X3 =-2
2X1 + 4X2 - X3 =3
-4X1 + X2 + 7X3 =10
(2) Using elementary row operations investigate the consistency of the following systems.
(a) 2X1 + 4X2 - 2X3 = 0
3X1 + 5X2 =1
(b) X1 - X2 + 2X3 =4
X1 + X3 = 6
2X1 - 3X2 + 5X3 =4
3X1 + 2X2 - X3 =1
(3) consider the system
X1 + 2X2 + 3X3 = a
2X1 + 5X2 + (a+5)X3 = -2+2a
- X2 + (a^2 - a)X3 = a^2 - a
