Tetrahedron - Wikipedia, the free encyclopedia
The tetrahedron is the three-dimensional case of the more general concept of a Euclidean simplex. . 9 A law of sines for tetrahedra and the space of all shapes of tetrahedra; 10 Applications . 11 See also; 12 References; 13 External links . In a trirectangular tetrahedron the three face angles at one vertex are right angles .
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What does plain mean?
2. plain clear to the mind; evident: to make one's meaning plain. 3. plain . a plain face. 8. plain without intricacies or difficulties. 9. plain with little or no embellishment or decoration: . 10. plain without a pattern, figure, or device: a plain fabric. 11. plain not rich, highly seasoned, or elaborately prepared, as food. 12. plain .
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What is a ten sided figure called
A two-dimensional shape with ten sides is a decagon. A three-dimensional object with ten faces is a decahedron. A ten sided . What is a 12 sided figure called?
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