solve the following inequality 4x-3/x+4 less than or equal too 3

I think you mean:

(4x-3)/(x+4) ≤ 3 , clearly x≠-4
4x-3 ≤ 3(x+4)
4x - 3 ≤ 3x + 12
x ≤ 15

make a rough sketch of
y = (4x-3)/(x4) and y = 3

you will see that (4x-3)/(x+4) ≤ 3 for

-4 < x ≤ 15