Distributing
Start with any three numbers.
4
6
8
Three ways to count the squares.
4
6
8
1. One at a time.
1, 2, 3, 4, 5, 6, …, 54, 55,
56.
2. As two rectangles:
(4 ´ 6) + (4 ´ 8) = 56
3. As one rectangle:
4
6 + 8
4´(6 + 8) = 56