It depends on whether you are counting the large main trriangles or counting all of the other triagles formed when drawing the just the Maine triangles. I counted 8 main triangles in a regular eneágono.
no triangles
Find out the number of matchsticks that the learners would need to build 40 triangles
10
the answer is pyramid
Infinitely many. Having found one triangle, you can find infinitely many similar triangles.
4 triangles make 1 hexagon. (easy way to find out how many triangles there are in a polygon- take number of sides of the polygon, subtract 2 from it, that's your answer!)
As many as she wants.
there are 27 triangles in a triangle
There are 15 triangles in a 17-agon
15 triangles
15 triangles!!!!!!!!!!
it has 13 triangles