You are probably thinking in the same way Lili does in this video:

She is assuming that because 3 • 5 is represented by a five by three rectangle of red tiles, 5 • 3 will be, too. This is only true if the commutative principle that is true for natural number multiplication, is also true for multiplying red numbers. 

Because we want to keep as many things about arithmetic the same, it makes sense to assume multiplication is commutative when red numbers are involved. 

In the next video we will see another reason to represent 5 • 3  by a rectangle of red tiles.

☐ I'd like to see the next video.

☐ I'd like to review an earlier video.