nilai x, y, z dari persamaan 2x+3y+z-6=0 3x+2y+z-7=0 x+2y-z-5=0

4x + 6y + 2z = 12
9x + 6y + 3z = 21
--------------- -
-5x - z = -9
5x + z = 9

3x + 2y + z = 7
x + 2y - z = 5
--------------- -
2x + 2z = 2
x + z = 1

5x + z = 9
x + z = 1
---------- -
4x = 8
x = 2

x + z = 1
2 + z = 1
z = -1

2x + 3y + z = 6
2(2) + 3y -1 = 6
3 + 3y = 6
3y = 3
y = 1

nilai => {2, 1, -1}