The following is an introduction to the square:

A square is a special parallelogram. That is, a group of parallelograms with equal adjacent sides and a right angle is called a square, also known as a regular quadrilateral.

A square has all the characteristics of a rectangle and a diamond.

definition

A parallelogram with a right angle and a set of equal adjacent sides is a square.

Decision theorem

1: A diamond with equal diagonal lines is a square.

2. Diamonds with right angles are squares.

3: Rectangles with diagonal lines perpendicular to each other are squares.

4. A set of rectangles with equal adjacent sides is a square.

5. A set of parallelograms with equal adjacent sides and one angle at right angles is a square.

6. A parallelogram with vertical and equal diagonals is a square.

7: Quadrilaterals with equal diagonals and bisecting each other vertically are squares.

8: A set of quadrilaterals with equal adjacent sides and three right angles is a square.

9: A quadrangle that is both a diamond and a rectangle is a square.

Refer to Baidu Encyclopedia-Square for the above information.