This is a nice cute puzzle with a “small” trick – I took this from the book “The Moscow Puzzles” by Boris A. Kordemsky (Puzzle #175).
In the diagram, 3 matches are connected with balls of plastic to make an equilateral triangle. Can you form 7 such triangles with 9 matches?
Seven Triangles
As always, please send your answers directly to me at alokgoyal_2001@yahoo.com. If you like the puzzle, please share it with others. If you have interesting puzzles to share, please send them to me at my e-mail given above.
Happy thinking!
Yes, in 3d. Taking the existing triangle as the mid plane, with three matches more on each side you can create two pyramids that share the existing triangle as the base. Total of six external face triangles and one common base triangle.