Solve the following systems:

1) x+z=2
2x+y=3
X-y+z=1

z = (2-x)

y = (3-x)

x -(3-x) +(2-x) = 1

x - 3 + x + 2 - x = 1

x - 1 = 1

x = 2
z = 0
y = 1