The face of a triangle IS a triangle!

A triangle has only 1 face.

One face that is the equilateral triangle.

One face that is the equilateral triangle.

One face that is the equilateral triangle.

One face that is the equilateral triangle.

a triangle has 1 face but if you mean a pyramid (3-D triangle) it has4 but a (a 3-D triangle with a square bottom) it has 5.

The face of a triangle is the flat surface of the solid figure.

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A face is a side of a 3 dimensional figure. So, the number of faces a triangle would be 0.