Whoa, I have no idea what some of these letters are coming from? Are they all integers or what? e is usually reserved for the exponential x is usually for real numbers and m and n are usually for integers, but I am hoping you have just run out of good numbers to use and all of these are just arbitrary integers.

mod n iff

so if you know a,b,m all fixed integers.

you just need to choose n to be a divisor of

Then you will get the desired congruence mod n

(mod n)