Answer:
6
Step-by-step explanation:
1) 4x-7y=3
x-7y=-15
2)4x-7y=3
-(x-7y=-15)
3) 3x=18
6) Divide by 3
7) x=6
a big fat C**K
x=2-y-z
x=5/2-y/2+z/2
x=-2+y-z