This Problem Set is a part of the Lesson 18, Unit 6, Grade 7. In this lesson, students examine the slices resulting from cuts made that are not parallel or perpendicular to a base or face. The slices were made either parallel or perpendicular to a base (or, in the case of a right rectangular prism, a face) of a right rectangular prism and right rectangular pyramid. Students describe polygonal regions that result from slicing a right rectangular prism or pyramid by a plane that is not necessarily parallel or perpendicular to a base.