Triangles in Photography to me are a combination of leading lines and triangles themselves, however sometimes these triangles can also be used for a frame, or for them to just be there to make the image more interesting. These triangles are quite tricky to find sometimes, but they sure do make the image look way more organized when you find the 'harder to find' triangle in the image. There are some which you can straight away spot, there are also some which are used as a frame, and also some which are hidden but are still there. EXAMPLES HERE THEY COME!
This is the easiest triangle to ever find in an image. The triangle is right in the center-towards-the-right part of the image. It is the roof of the house. And if you look a bit closer, you can see that the antenna on the middle bottom has two triangles inside it too.
There are many triangles in this image, some of them are outlined already just so you can see them. The woman's arms both have triangles in them, and one on her left shoulder (to us that is on the right) there is a curvier triangle too. I can also see one on her neck, at the very bottom of them, where the bones are.