A square has all sides of the same length. The area of a square is the product of its width times its height, and for a square, these numbers are the same. So, any whole number which is a product of a number with itself is called a square number. For instance, 3 x 3 = 9 so 9 is a square number.
Not all numbers are square numbers, because we cannot find a whole number to multiply by itself to make 10,
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