shapes

desa · 2005-11-27 04:33:15

what solid has got the following

8 edges
5 vertices
and 5 faces.
1 of these faces is a square.
from desa

mathsyperson · 2005-11-27 05:58:10

A square-based pyramid would work. I can't think of any others, but there might be some. I doubt it, though.

darthradius · 2005-11-28 15:48:19

I think that's the only one...since one square face is given, that accounts for four vertices...then there is only one other to work with, so you need a pyramid.

michael6 · 2006-10-31 00:14:00

my daughter would like to know what object has 6 vertices&10edges plus what has 8 faces&12 vertices

mathsyperson · 2006-10-31 02:24:07

The first object could be pentagonal pyramid. The pentagon would have 5 edges and vertices, and there would be another vertex somewhere else, with 5 edges joining it to each vertex on the pentagon.

The second could be a hexagonal prism. Two hexagons, each with 6 vertices (making 12 in all), and each vertex joined up with another vertex on the other hexagon. There are 6 faces made up by the edges joining the two hexagons, and another 2 faces made by the hexagons themselves.

There might be alternate answers to both of these.

All_Is_Number · 2006-10-31 02:39:35

mathsyperson wrote:

The first object could be pentagonal pyramid.

Wouldn't a pentagonal pyramid have six sides?

mathsyperson · 2006-10-31 05:09:45

No, that has 10 sides, like the question asks for. The pentagon has 5 sides, and then there are 5 more sides joining each corner of the pentagon to the pyramid's apex.

Math Is Fun Forum

#1 2005-11-27 04:33:15

shapes

#2 2005-11-27 05:58:10

Re: shapes

#3 2005-11-28 15:48:19

Re: shapes

#4 2006-10-31 00:14:00

Re: shapes

#5 2006-10-31 02:24:07

Re: shapes

#6 2006-10-31 02:39:35

Re: shapes

#7 2006-10-31 05:09:45

Re: shapes

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