MP0149: Add 9 to have 18 Triangles admin January 17, 2021 Leave a Comment on MP0149: Add 9 to have 18 Triangles Posted in Matchstick, Matchstick - Triangular We use 15 matches to create 7 triangles (5 small 2 medium). Can you add 9 more matches so that there are 18 triangles in total? Show the answer Hide the answer Share this:FacebookXLike this:Like Loading... Author: admin