Sankaku puzzles are a geometric based logic puzzle that focuses on finding the area of a triangle. The goal of each puzzle is to connect three dots to form a triangle with the specified area. Sankaku puzzles are the creation of Naoki Inaba, a prolific Japanese puzzle creator. I first discovered these puzzles several years …

# Triangle Puzzles

This tricky triangles puzzle has been around for over a century – can you arrange these eight sticks to form exactly four triangles and two squares? The original puzzle was meant to be solved with matchsticks, but I don’t think I need to explain why I won’t be giving my students matchsticks to play with… …

It’s November which means it’s finally time to pull out this Triangular Turkey puzzle for Thanksgiving. How many different triangles can you find in this picture of a Thanksgiving turkey? I ran across this triangular turkey puzzle in a Martin Gardner book (Perplexing Puzzles and Tantalizing Teasers) this summer, and I knew I had to …

I’m excited to get back to featuring a new puzzle of the week every week in my classroom this year. A new puzzle I have prepped for this year is called Three of Five. Three of these five figures fit together to create a triangle. Which ones are they? I ran across this puzzle in …

Looking for a challenge? Check out this page of Make It Pythagorean Puzzles. Insert the same digit (in any manner of your choosing) to each side of the triangle to form a right triangle. I ran across these interesting puzzles in Golf on the Moon by Dick Hess (Dover Publications).

The Parts of a Whole Puzzle gives students five shapes that must be arranged to form a triangle whose three sides are of equal length. In other words, form an equilateral triangle. I would have renamed this as the Equilateral Triangle Puzzle, but I have already shared a different equilateral triangle puzzle on my blog …

This equilateral triangle puzzle comes from Puzzle Box, Volume 1 from Dover Publications. This is the first book in a series of three puzzle books that are edited by the Peter and Serhiy Grabarchuk. This specific puzzle is by Richard Candy. Each volume has 300 puzzles, and I have found over a hundred puzzles between …

I found this dragon puzzle to practice special right triangles online, and I fell in love with it. Each of the triangles is a special right triangle. I did a bit of research, and I was able to find the original source. I also found the same problem in McDougal Littell’s Geometry: An Integrated …