Posted by donald on .
3x+y+2z=1
x+2yz=8
3xy3z=18
after I isolate x what is the 2nd equation

math 
Steve,
depends on how you isolate x.
isolate it from the first equation and you have 1/3 * (1y2z) + 2y z = 8
1y2z + 6y 3z = 24
5y 5z = 23
Anyway, you end up with (x,y,z) = (15, 6, 11)