



 
Hi, Here is my display of dots. What if you circle three dots in each corner. There are 3 dots in each circle and you have removed 4 dots from each side so you have the number sentence $4 \times 3 + 4\times(5  4).$ What if you walk around the square in a counterclockwise direction starting at the upper right corner. Every time you get to a corner you circle the corner dot and the next dot after it. You have 4 groups of 2 dots that are circled and 4 groups of (5  3) dots that are not circled. Thus you have $4 \times 2 + 4 \times 2$ dots. What about an n by n square? For the example given with the corner dot being circled you now have 4 dots circled and on each side all but 2 are not circled. Thus you have $4 + 4 \times (n  2)$ dots. See if you can mimic the two techniques I used but with an n by n square. Penny  


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