## The Missing Square Trick and Evil Ed

My old college roommate Ed is evil. But in a good way.

In my undergraduate days at UC Irvine, one of my roommates was Ed K. We went through all kinds of adventures together at school, in Las Vegas, in Miami, and working at Disneyland. He’s still one of my very best friends.

But Ed knows exactly how to distract me. Ed sent me a link to a fascinating video of a magic trick that is related to geometry. Ed knows I love math and magic, and so I spent an hour playing and replaying the video to try and figure out how it was done. Evil Ed.

I still don’t know how the trick was done, but it reminded me of The Missing Square Puzzle Trick. Look at the image below closely. The top multi-triangle (made of four shapes) and the bottom multi-triangle (made of the exact same four shapes) both have area of 13 wide by 5 high. But the bottom multi-triangle has a missing 1×1 square! Where did it go?

The Wikipedia entry at https://en.wikipedia.org/wiki/Missing_square_puzzle explains the trick. Anyway, I think this may have something to do with the magic trick video Evil Ed sent me.