Proof to find the area of a square?

Answer 1

The unit of area "one square meter" or "one square foot" is DEFINED as the area of a square with sides of length 1 meter or 1 foot. This works for any unit of distance measurement. So we start with this definition. It follows that a square with sides of length n when n is an integer has area n2 square units because it can be divided into n*n= n2 small squares one unit on a side. For the area of a square with sides of fractional length, we can use a proof that calls upon similar polygons. This proves the area exists, it does NOT prove it is unique. To prove that, assume it is not uniqe and arrive at a contradiction.