Yes I know, this is just a meme.
Altho another approach is to imagine what the area of a square with the sides (a+b) would be: if 'a' is smaller than 'b', then there will be a small square with sides 'a' so it's a², a larger square with sides 'b' which will be b² and i'll be touching the a² at one vertex, then two rectangles with sides 'a' and 'b' connecting the a² and b² at two-two sides, filling out a bigger, (a+b)² square.
I hope this makes sense, it is much easier to see it than trying to describe it.
