



 
Hi Daniela. The term "face" normally applies to a twodimensional flat surface on a three (or more) dimensional object. So technically, it doesn't apply at all so you could say zero. On the other hand, a triangle may be one of the faces on such an object (such as a pyramid), so even though it doesn't have a face, the triangle itself represents one face of the object. Stephen La Rocque.  


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