For this, we kind of have to test points to solve it. First, we can test theh interval x<= -2. Plug in -2 and we get a negative value which works. Next, let's try -2<x<0. Plug in -1 and get a positive value which doesn't work.
Next try 0<=x<=7. Plug in any number like 4 and get a negative value which works.
Finally, try x>7. Plug in 8 for example and you would get a positive value. So the solution is
