This Problem Set is a part of the Lesson 15, Unit 3, Grade 6. Students extend their understanding of the coordinate plane to include all four quadrants and recognize that the axes of the coordinate plane divide the plane into four regions called quadrants (that are labeled from first to fourth and are denoted by roman numerals). Students identify the origin and locate points other than the origin, which lie on an axis. Students locate points in the coordinate plane that correspond to given ordered pairs of integers and other rational numbers.