if y=6 them we will have
3*6>2x
18>2x
x must be smaller than 9, because
18=2*9 => 18=18, and we doesn't respect the rule
now that we know that x<9 we have other 2 cases...
1. x is a natural number x can take values from the interval [0, 8]
2. x is a rational number, so it can take values from the interval [8, - infinite)