You are going to have to try a little harder. You are not seeing that the region you are describing is NOT bounded. If you have a picture in front of you, and it is bounded, then you are not describing it sufficiently. Please provide the entire problem statement. galactus gave it a try, including the limiting y-axis. Since you have declined this description, perhaps you can check for typos and take another shot at the ENTIRE problem statement. If you are not understanding the problem, you should not try to decide which parts of the problem are needed. Just provide ALL of it.