Description of the formula: In the formula, A is the side length of the square and S is the area of the square.

The area s is equal to a× a.

Square area = diagonal x diagonal ÷2

S= diagonal x diagonal ÷ 2

Square is a special parallelogram and a special rectangle. In the same plane: a quadrilateral with four equal sides and a right angle is a square. A set of rectangles with equal adjacent sides is a square. Diamonds with right angles are squares. The diagonal lines of a square are equal and bisected vertically.

It can be deduced that the side length of a square is a=√ area s.

Extended data:

The trial in the square:

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.

Baidu encyclopedia-square area calculation formula