To simplify this expression, we first need to find a common denominator for the fractions.

The common denominator for the first fraction is 3x, and for the second fraction is 2x.

So, the expression becomes:

((3x)(х-1) + 12(3x) + (2x)(2) - x) / (3x)(2x) + 8(3x)

Expanding:

(3x^2 - 3x + 36x + 4x - x) / 6x^2 + 24x

Combining like terms:

(3x^2 + 36x - x) / 6x^2 + 24x

Further simplifying:

(3x^2 + 35x) / 6x^2 + 24x

Therefore, the simplified expression is (3x^2 + 35x) / 6x^2 + 24x.