This trick is an extraordinary introduction to the power of algebraic thinking, and a reminder of what makes algebra so awe-inspiring.
A video Launch for this lesson is available in two parts. PDF of the lesson is below the videos.
Part 1. When using as a class launch, stop at 2:45 and let the class come up try to find their own counterexamples.
Part 2 – the solution to the magic trick.View Fullscreen