How many triangles does a hendecagon have?

Answer 1

6

Answer 2

If one of the sides of the hendecagon must coincide with a side of the triangle, then there are 11 triangles with a interior point as a common vertex. Alternatively, there are 9 triangles with the same side of the hendecagon in each triangle.

However, each of these triangles, for example, can be divided into two, and then they can be further divided. So the total number of triangles is any [large] number you like.

Answer 3

11