Answer:
- hexagon
- rectangle
- square
- triangle
- pentagon
Step-by-step explanation:
Only a straight line can be formed at the intersection of a plane with another plane. The faces of a cube are planes, so a 2-dimensional (planar) cross section of a cube cannot be a curve. It cannot be an ellipse or circle.
What polygons are possible?
The intersection of a plane with a cube can be a polygon with 3, 4, 5, or 6 sides. That is, the 2-D cross section of a cube can be ...
triangle, rectangle, square, pentagon, hexagon
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The attachment shows some possibilities.