can you do math by simply drawing?????

Answer 1

We were messing around with this at school the other day. It's just like binomial multiplication. It works on the same basis that algebra tiles do to model binomial multiplication with variables.

If you've ever used them you may have model problems like this with the tiles (x + 2)(x + 3). In the end you get large squares that represent x^2, rectangles that represent x and smaller unit squares that represent ones. Basically you'll have all the building blocks to get x^2 + 2x + 3x + 6. When they circle the two terms (from the intersecting lines) on the left to right diagonal, that's equivalent to the 2x and 3x terms above (or if you use FOIL, the O and I).

When we were deciding if it would work for all numbers, oringally we did it wrong and used that sort of thinking to find our mistake. Turns out we can't count all that well.

Answer 2

It really works. The number of intersections between x number of lines and y number of lines equals x times y (try it!).

Then what they do is multiply the ones digits for the ones digit of the product. Then multiply the tens digit of one number with the ones of the other number, and vice versa, and add the two, for the tens digit of the product. Etc. It's the same order as when you multiply two numbers out the long way.

Answer 3

my bf watched the video, tried it and it worked.
hard to draw the lines right with larger numbers.
and it is only for multiplication.

Answer 4

i just watched that video. I tried to do that but i screwed up.