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Can a polyhedron have following for its faces
(i) 3  triangles?
(ii) 4  triangles?
(iii) a square and four triangles?
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Question

Can a polyhedron have following for its faces
(i) 3  triangles?
(ii) 4  triangles?
(iii) a square and four triangles?

Answer

1) No.
2) Yes,
3) Yes.
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Solution

(i) For a polyhedron, minimum number of faces required are four, so three triangles cannot form a polyhedron.
(ii) Yes, a polyhedron can have 4 triangles as its faces, which is the case in a Tetrahedron.
(iii) Yes, a square pyramid is a polyhedron which has a square and four triangles as its faces.
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