Two steps forward

Two equilateral triangles share a vertex and have their bases on the same line. A third equilateral triangle is constructed from their apexes. Prove that its apex is also on that line.

Scroll down for a solution to this problem.


Solution by Dr Rick.

Visual solution

Solution without words by David Andriana.


2 steps forward
1 step back
To measure the progress
Ardeous and forward
When things are not smoothy
Like in a period of crisis
Sometimes it goes right
Sometimes it goes wrong
It’s a metaphor for a transition
Just stop or actively do it
Like the frog did to scale a water well


🤞 Don’t miss these puzzles!

Subscribe to the weekly geometry puzzle e-mail.

Leave a Reply

Your email address will not be published. Required fields are marked *

Optionally add an image (JPEG only)