9x/(x^2-100) >= 0
Something happens at x = 0, -10, and 10
Test: x = -100, -5, 5, 100
x = -100 makes it -
x = -5 makes it +
x = 5 makes it -
x = 100 makes it +
We can't hit x = -10 because that would make the bottom of the equation 0, so at -10 there's a (
We can hit x = 0, so there's a ] at 0
We can't hit x = 10 because that would make the bottom of the equation 0, so at 10 there's a (
(-10,0], (10,Infinity)