A perfect rectangle is a rectangle that can be divided into squares of different sizes.
If a perfect rectangle is specifically a square, it is analogously called a perfect square. Its creation is referred to as squaring the square.
A rectangle that is not perfect is also called an imperfect rectangle.
For perfect squares to exist, it is generally not sufficient that the sum of square numbers is mathematically a perfect square. The numbers 1 and 4900, for example, satisfy this condition; they are, incidentally, the only square numbers that are also perfect squares. For them, the following holds:
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However, it is not geometrically possible to divide the corresponding 70x70 square into 24 squares.
Many mathematicians have been involved in the discovery of perfect rectangles and perfect squares.
Below is a selection of important discoveries in this field.
Among the numerous perfect rectangles and squares, the following selected examples are intended to highlight some special features.
(The numbers in the squares indicate their respective side lengths.)