Solve for Z
A= X+Y+Z/3
AZ=3A-X=Y
BZ=3A+X+Y
CZ=-3A-X-Y
DZ=3A-X-Y
A= X+Y+Z/3
AZ=3A-X=Y
BZ=3A+X+Y
CZ=-3A-X-Y
DZ=3A-X-Y