[grexam]

well the second problem can be solved by trial n error method

x+y=4
y+z=8
z+x=6

Assume values x=1,y=3,z=5
substitute them in each
1+3=4
3+5=8
5+1=6
and finally 6-5-1=0

hope this works out what do u think?????if any other way plzz do post