Which figure is not completely constructed from polygons?
A. tetrahedron
B. pyramid
C. cylinder
D. cube
11 Answers

cylinder

Cylinder.
Polygons are basically two dimensional objects made up of straight lines.
Although a circle is also a two dimensional object, it is made up of a “curved” line as opposed to a straight one.
Hence, since the cylinder has two circles it is the only one not completely made up of polygons.

Polygons are composed of a finite sequence of straight line segments.
The cylinder does not, it has two circles (not polygons). You may say that could unwrap the lateral side into a rectangle.
The others have triangles, and/or squares, which are polygons.

C. Cylinder—>not formed from polygons

A cylinder. The faces are circles which are not polygons.

Cylinder is not a polygon because it has no straight sides

C. Cylinder, because its curved face is not a polygon. Note that the curved face can be unfolded into a rectangle, but it requires that you artificially introduce an edge that is not present in the solid figure.

A cylinder because it has no sides.
Source(s): Engineering graduate 
cylinder

cylinder