Diketahui sistem persamaan, x + 2y = -4, 2x + z = 5, y - 4z = -7

x + 2y = - 4
x = - 2y - 4

subtitusi
2x + z = 5
2( - 2y - 4 ) + z = 5
- 4y - 8 + z = 5
- 4y + z = 5 + 8
- 4y + z = 13

eliminasi
y - 4z = - 7
- 4y + z = 13 |×4
maka
y - 4z = - 7
- 16y + 4z = 52
----------------------(+)
- 15y = 45
y = - 3

subtitusi
y - 4z = - 7
- 3 - 4z = - 7
- 4z = - 7 + 3
- 4z = - 4
z = 1

subtitusi
x + 2y = - 4
x + 2(-3) = - 4
x - 6 = - 4
x = - 4 + 6
x = 2

hp = ( 2, - 3 , 1 )