5y-8z=-19 5x-8z=6 3x-2y=12

5y – 8z = -19
5x – 8z = 6
—————— –
5y – 5x = -25 | kali 2
3x – 2y = 12  | kali 5

10y – 10x = -50
-10y + 15x = 60
——————–+
 5x = 10
x = 2

substitusikan untuk mencari y
3x – 2y = 12
3(2) – 2y = 12
6-2y=12
-2y=6
y = -3

5y – 8z = -19
5(-3) – 8z = -19
-8z=-4
z = 1/2