1) How do i write the answer in interval notation for (x-5)(x-11)>0 I got (5,infinity)U(11,infinity) webwork said it is incorrect too, so can anyone help me out what mistake i made for those two problems?

2)how will the problem be solved for the inequality in interval notation for -2x^2<18

3)also for the problem -x^2+4x(equal or > to)0 ?