Colin the Mathmo on Nostr: So here's a nice puzzle from Donald Bell. It's a lovely question to show that the ...

So here's a nice puzzle from Donald Bell.

It's a lovely question to show that the shaded area in the first image here has area one fifth of the original square.

Using the same construction, joining vertices to midpoints, does the same thing hold true for a general quadrilateral?

How would you prove it? Do you have a counter-example?

#Geometry #Puzzle