Crossposted from https://mbin.potato-guy.space/m/[email protected]/t/157668

From the description:

This fruity math meme has been floating around the internet for some years now, but all is not what it seems! Developed by actual serious mathematicians, it involves some advanced techniques. Elliptic curve theory can be used but, here, I find the solution using just basic algebra. You don't need to know the advanced theory but, in the process, it does reveal the tricks, structures, and beauty underlying elliptic curves.