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Strange pyramid (Posted on 2004-05-03) Difficulty: 3 of 5
On Pythagorean Pyramid we tried to build a tetrahedron out of four equal right angled triangles, but the attempt fell flat (pun intended!).

Is it possible to have a tetrahedron built out of right angled triangles, dropping the condition that all triangles be the same? Can you manage to have three equal faces? Or maybe two pairs of equal faces?

See The Solution Submitted by Federico Kereki    
Rating: 3.0000 (2 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
re(3): Short answer to part 1. | Comment 9 of 10 |
(In reply to re(2): Short answer to part 1. by broll)

Perhaps I'm not familiar with the shape of a "cereal packet". I assumed a rectangular solid. Even with the revision, if the cut is perpendicular to an edge, that would create just another rectangular solid (or actually two rectangular solids).

If it is indeed cutting off a corner of a rectangular solid, it's not perpendicular to either an edge or a face, and the cut itself is not a right triangle.

Edited on March 1, 2016, 7:34 am
  Posted by Charlie on 2016-03-01 07:32:01

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