Session 9, Part C:
Cross Sections

In This Part: Slicing Solids | Polygon Shadows

 You've looked at some of the "two-dimensional" properties of three-dimensional figures: their surfaces (nets) and their cross sections. Solid figures also cast two-dimensional shadows. Do you think you can recreate a solid by knowing what shadows it casts?

 Problem C5 A solid object casts a circular shadow on the floor. When it is lit from the front, it casts a square shadow on the back wall. Try to build the object out of clay. Can you name it?

 Problem C6 A solid object casts a circular shadow on the floor. When it is lit from the left, it casts a triangular shadow on the back wall. Try to build the object out of clay. Can you name it?

 Problem C7 Suppose the object casts a circular shadow on the floor, a square shadow when lit from the front, and a triangular shadow when lit from the left. Try to build the object out of clay. Can you name it? Note 4

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