triangles, or other polygons. A cylinder with parallel

In figure 14-38, several three-dimensional figures

ends would unroll into a parallelogram. A cone would

are shown. Try to form a mental picture of how these

unroll into a section of a circle. However, warped

figures would look if they were unfolded or unrolled

surfaces cannot lie flat. Double-curved surfaces present

and laid out in a flat plane. The polyhedrons, of course,

a similar problem.

would be merely a system of connected squares,

14-24