This week I learned how to model an algebraic expression with tiles. First you write half of the equation on the top and the rest on the side. You then see what the tiles are representing, if you have 2 long bars then that would make a big square. If you have a long bar and a cube that makes a long bar. Coloured in tiles are positive and white tiles are negative.
How can you tell if the resulting algebra tiles found inside the rectangle should be shaded in or not?