To simplify this expression, we will first find a common denominator for both fractions.

For the first fraction, the denominator is x(5x-3y) and for the second fraction, the denominator is y(3y+5x).

The common denominator for both fractions is their product: x(5x-3y)*y(3y+5x) = xy(5x-3y)(3y+5x).

Now, we rewrite the fractions with the common denominator:

(x(y(5x-3y)) - (x)(y)(5x-3y)) / (xy(5x-3y)(3y+5x)) + (y(5x-3y) - (y)(5x-3y)) / (xy(5x-3y)(3y+5x))

Simplifying further:

(xy(5x^2 - 3xy) - xy(5x^2 - 3xy)) / (xy(5x-3y)(3y+5x)) + (y(5x-3y) - y(5x-3y)) / (xy(5x-3y)(3y+5x))

Now, both terms in the numerator of each fraction will cancel out:

0 / (xy(5x-3y)(3y+5x)) + 0 / (xy(5x-3y)(3y+5x))

Therefore, the simplified expression is:

0