1. The problem statement, all variables and given/known data Solve simultaneously: 6(x + y) = 5xy, 21(y + z) = 10yz, 14(z + x) = 9zx 2. Relevant equations - 3. The attempt at a solution Obviously one of the solution is (0,0,0) But I'm more interested in finding the other. Expanding these three equations , I get - 6x+6y=5xy 21y+21z=10yz 14z+14x=9zx But what now? I've no experience solving these type of systems . Please give hints.