These triangles belong to three different families.
All the triangles in the same family are the same shape.
But they may not be the same size or the same way up.
Can you sort them out and explain how you did it?
You could print off pictures of the triangles (here as a Word document or here as a pdf), then cut them out and sort them practically. Or if you prefer, you could use the interactivity below to try out your ideas: