Write the augmented matrix for each of the following systems of linear equations.
(a) x - ly = 5
2x + y = 1
(b) x + 2y = 0
y = 1
(c) x - y + z = 2
x - z = l
y + 2x = 0
(d) x + y = 1
y + z = 0
z - x - 2