The below figure shown the total no. of triangles is 8+8+2+6+4=28

The main triangle shown is in the given figure and this the total no. of triangle is 15. remaing triangle we can find out in the drawing the triangle in the image.

First mark each rectangles 1, 2 and 3 after we can cube of 1 +8+27=36 we get the answer

3+3+3=9 triangle 

Triangle ABD +Triangle ADC =2

Same as 2+2+2=6

And Triangle ABC=1 

So that total no of triangle in this figure is 9+6+1=16