Is a concave pentagon having three collinear vertices possible?
回答 (3)
2018-09-19 10:14 am
Yes. For example, draw the letter M with a line across its bottom. That is a pentagon. Draw it so that the bottom left corner and middle of the valley point and the top of the right peak are all in line.
2018-09-19 10:03 am
no
2018-09-19 9:40 am
It can't have three collinear vertices, which is readily proven. The intersect of a convex solid and a space is a convex region in that space. Any line that passes through it produces a single line segment, bounded by no more than two points.
收錄日期: 2021-04-24 01:08:25
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