Solve math problem please help !!!!!!

Subtract and simplify as much as possible: x/x^2-16 - 3/x^2+5x+4

I really need your help as soon as possible

x/x^2-16 - 3/x^2+5x+4
=> {x/(x+4)(x-4)} - {3/(x^2 + 4x + x + 4)}
=> {x/(x+4)(x-4)} - {3/(x(x+4) + 1(x+4))}
=> {x/(x+4)(x-4)} - {3/(x+1)(x+4)}
=> {x(x+1) - 3(x-4)}/(x+1)(x+4)(x-4)
=> (x^2 + x - 3x +12) / (x+1)(x+4)(x-4)
=> (x^2 - 2x +12)/ (x+1)(x+4)(x-4)
This cannot be simplified further. Hence, this is the answer