Solutions:
x=y=z=1
x=y=z=-2
xz+y=2 (a)
yz+x=2 (b)
yx+z=2 (c)
from (a) y = 2-xz
sub into (b) and (c) gives
z+2x-x2z = 2 which factorises to give z(1+x)=2 (x /=1) (d)
x+2z-z2x = 2 which factorises to give x(1+z)=2 (z /=1) (e)
Substitute x from (e) in (d) gives:
z(1 + 2/(1+z))=2
z2 + z – 2 = 0
z = 1 or -2
x = 1 or -2
y = 1 or -2