Nilai (x - y) dari sistem persamaan linear x + y + z = 2 3y - 4z = -5 6z = 3

6z = 3
 z = 3/6 = 1/3

3y - 4z = -5
3y - 4(1/3) = -5
3y - 4/3 = -5
        3y = -5 + 4/3
        3y = -11/3
          y = -11/9

x + y + z = 2
x - 11/9 + 1/3 = 2
x - 8/9 = 2
       x = 2 + 8/9
       x = 26/9

x - y =26/9 - (-11/9) = 37/9