Tolong dong jawabannya dengan caranya

z = 2
3y = 23 - 4z
3y = 23 - 4.2
3y = 23 - 8
3y = 15
y = 5

2y - 4x = 4
2y - 4 = 4x
2.5 - 4 = 4x
10 - 4 = 4x
6 = 4x
x = 6/4 = 3/2