1/x - 1/ y=4 ... A
1/x - 1/z=5 ... B
1/x + 1/z=3 ... C
B + C => 2/x=8 from this we can get x= 1/4
Substitute x in Equation A
1/(1/4) - 1/y=4
4 - 1/y = 4
0 = 1/y
which is impossible because if we continue it
0 * y = 1/y * y
0=1 which is definitely not true
