I see it a little differently.

3X-1=mod6

there is no number you can put in X to get integer multiples of 6 on the left.

One example. 3(7/3)=1 mod6 => 7=1 mod6 ; this would be correct, but it is not a solution since 2.3333333333333333333333333333 is not an integer.

Correct me.

__________________