if the range for a problem is y<7 what does y mean?

Question

I've been trying to figure out what number y is supposed to stand for

Answer 1

When you graph a function (something like y = x+3 or y = x^2 + 3x - 7), the domain is the list of possible values for x (the horizontal axis) and the range is the list of possible values for y (the vertical axis).

In this case y < 7 means y can be anything as long as it's less than 7.  There are many equations that would generate this answer.  One such equation is y < -x^2 + 7