In the set of ordered pairs {(-2, 0), (0, 6), (2, 12), (4, 18)}, the domain is the set of the first number in everypair (those are the x-coordinates): {-2, 0, 2, 4}. Therange is the set of the second number of all the pairs(those are the y-coordinates): {0, 6, 12, 18}. There you go :)