Math problem

Hay guys how do I solve for this? a,b,c,d are constants and I have to solve for v,x,y,z.

v (x + y + z) = a
x (v + y + z) = b
y (v + x + z) = c
z (v + x + y) = d

>>8
Ok, real solution here:

vx^2yz + vxy^2z + vxyz^2 = axyz
v(x^2yz + xy^2z + xyz^2) = axyz
v(xyz(x + y + z)) = axyz
v = a/(x+y+z).

Similarly, x = b/(v+y+z), y = c/(v+x+z), z = d/(v+x+y).