This problem is adding and subtracting rational espressions with different denominators.

4x/[2x^2 + x -10] - 9x/ [x^2 + x - 6] Factor the denoms -->

Factoring is a process of un-FOILing:

2x^2 + x -10 = (2x +5)(x-2)

x^2 + x - 6 = (x+3)(x-2)

Since both denoms include (x-2), we need it just once as a factor for the common denom -- (2x+5)(x-2)(x+3)

Now multiply each fract ion by the common denom to find the new numerators. Combine the new numerators and keep the common denom.