We saw previously that drawing pictures is a good way to think about multiplication.
Multiplying is really just adding a whole bunch of things together, as long as they’re the same size. The little boxes showed that, but it got a little crazy once we used bigger numbers.
So, let’s keep on with the pattern of pretending, by trying out 14 x 7. Since I don’t actually know 14 x 7, I will break it down: 14 is really just 10 and 4. So I’ll split that side length in my picture. Then I have two little rectangles…10×7 and 4×7! I can do that!
(and if you want to get really fancy/technical, we did just demonstrate the distributive law!)
867 = 800 + 60 + 7
39 = 30 + 9
BAM! Still annoying…but addition is better than multiplication.
Now…how does this all help with the lattice model? That ugly beast of multiplication…