To simplify the expression, we need to combine like terms and simplify any fractions.

First, let's simplify the fractions separately:

11 - 2x / 3x + 1 = (11 - 2x) / (3x + 1)

5x - 10 / 3x - 1 = (5x - 10) / (3x - 1)

Now, let's combine the fractions:

(11 - 2x) / (3x + 1) + (5x - 10) / (3x - 1)

To add fractions, we need a common denominator. In this case, the common denominator is (3x + 1)(3x - 1).

So, we multiply the first fraction by (3x - 1) / (3x - 1) and the second fraction by (3x + 1) / (3x + 1):

[(11 - 2x)(3x - 1)] / [(3x + 1)(3x - 1)] + [(5x - 10)(3x + 1)] / [(3x + 1)(3x - 1)]

Expanding and simplifying:

[33x - 11 - 6x^2 + 2x] / [(3x + 1)(3x - 1)] + [15x^2 - 5x - 30x - 10] / [(3x + 1)(3x - 1)]

Combining like terms:

[-6x^2 + 35x - 11] / [(3x + 1)(3x - 1)] + [15x^2 - 35x - 10] / [(3x + 1)(3x - 1)]

Now, we can add the fractions:

[-6x^2 + 35x - 11 + 15x^2 - 35x - 10] / [(3x + 1)(3x - 1)]

Simplifying further:

[9x^2 - 26] / [(3x + 1)(3x - 1)]

So, the simplified expression is (9x^2 - 26) / [(3x + 1)(3x - 1)].