Question

2x+y+2z=2
x+z=0
y-z= 3

Answer 1

z=y-3

x+y-3=0 -> x= -y+3

2(-y+3)+y+2(y-3)=2
-2y+6+y+2y-6=2
y=2 por lo que
z=2-3 ->z=-1
x=1