I think you mean (just saying "f(x)/g(x)" is very vague) that you want to make a single fraction of 3- 4/(x-2). Change to "common denominators" which here is the only denominator, x- 2, and subtract: 3(x-2)/(x-2)- 4/(x-2)= (3x-2- 4)/(x-2)= (3x- 6)/(x-2).