FIRST-- I can not figure out how to enter a problem containing Set-Builder Notation? Specifically the use of the symbol in my math book "|" which means "Such That" here is an example. (a,b)={x|a<x<b} it give me an error with this form of notation Second --How do you plot on a number line, also called real line, points, line segments, rays, or lines? Third(and final for today) -- is there any way to sketch regions on the Cartesian coordinate system for problems like absolute(y)<1, y=1, or x>0 these problems will fill in areas of the plot in the quadrants? Ok after some 30+hrs of research on my own and with my fellow students I turn to you for help now. . . . Please help, and thank you.