Multiply a whole side by 4 and then subtract 4 corners. - Mrs. Shapiro, Multiply a whole side without 2 corners by 4, and then add the 4 corners. - Jose, Multiply a whole side without 1 corner by 4. - Hezam, Add a whole side on the top and on the bottom together, and then add a side without 2 corners on the left and on the right. - Denzel, Add a whole side on the top, plus two sides without 1 corner, and 1 side without 2 corners. - Aamira, Multiply a whole side by itself and subtract the product of a whole side without 2 corners multiplied by itself. - Nicolas,

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