Question

What is the solution set of {x | x < -5} ∩ {x | x > 5}?

Answer 1

just a closed circle on 2
an open circle on 2 and arrows pointing out
the entire number line
no solution

Answer 2

Well, every member, x, of the intersection must have the property that
x < -5
and
x > 5

What values of x have this property?

Answer 3

from -5 down