Can the fill in statement be explained to me? I'm not really sure what it's even saying.

To solve a rational inequality, we factor the numerator and the denominator into irreducible factors. The cut points are the real ---Select--- # of the numerator and the real ---Select--- of the denominator. Then we find the intervals determined by the |---Select--- Let *) , and we use test points to find the sign of the rational function on each interval. r( x ) = ( x + 4) (x - 1) (x - 7)(x+ 9) Fill in the diagram below to find the intervals on which r(x) 2 0. Sign of -9 -4 1 7 x + 4 ? + ? + ?+ ? + x - 1 ?4 X - 7 ?4 x + 9 ?+ ?# (x + 4)(x - 1) (x - 7)(x+ 9) ?+ 74 From the diagram we see that r(x) 2 0 on the intervals (Enter your answer using interval notation.)