Date: 04/01/97 at 21:26:24 From: Tyler Hope Subject: Cube Edges How many edges does a cube have? My dad says that there are six edges on a cube, but I think there are twelve edges. I know that a cube has six sides, but edges and sides are not the same.
Date: 04/02/97 at 00:19:42 From: Doctor Steven Subject: Re: Cube Edges There are 8 vertices on a cube, and 6 faces, so there are 12 edges or lines connecting one vertex to another, on a cube. There are eight vertices because you have one square on the bottom and another square above it and you connect the two squares with edges to form a cube. Note that the bottom and top squares both have four edges, so to connect the squares you must add four more, one at each of the corners. This makes 12 edges in total. The top and bottom squares make two faces and when you add the four new lines you add 4 more faces, for a total of 6 faces. Hope this helps. -Doctor Steven, The Math Forum Check out our web site! http://mathforum.org/dr.math/
Date: 04/16/97 at 00:19:42 From: Doctor Chuck It is often hard to see these problems in your mind. Whenever I have trouble visualizing a three-dimensional object, I find that the best thing I can do is grab some play-dough or clay and MAKE the object so that I can poke and prod at it. So, a good way to solve your problem is to find a box (like a shoebox or a cereal box, which is a stretched cube), take a marker pen, and number each of the edges. The beauty of this is that you don't just convince yourself that a box (like a cube) has 12 edges, you also can show this box to your father and convince him, too. -Doctor Chuck, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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