×,y,dan z adalah penyelesaian dari sistem persamaan × + 2y=-4 2× + z=5 y - 3z=-6 Tentukan nilai ×,y,z

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

2x + z = 5

y - 3z = -6

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

Eliminasi
-4y + z = 13 |x3|
y - 3z = -6 |x1|
_____________
-12y + 3z = 39
y - 3z = -6
----------------------- +
-11 y = 33
y = 33 / (-11)
y = -3

y - 3z = -6
-3 - 3z = -6
-3z = -6 + 3
-3z = -3
z = 1

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

maka
x = 2
y = -3
z = 1