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?
As always, please send your answers directly to me at firstname.lastname@example.org. 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.