A stop sign?
There are 6 triangles in an octagon
An octagon is a shape with eight sides.
Eight triangles of equal size form a regular octagon.
No but they will make a hexagon
8
No, it is not possible.
Octagon.
triangles
Six coplanar lines could not form an octagon because an octagon has eight sides, so six lines would not be sufficient to make an octagon.
making an octagon using diamond shapes
No not just any shape that has 8 side can be called an octagon. An octagon has straight lines that make up a closed bounded shape.
8 sides