Rectangle, a mathematical term, is a parallelogram with right angles called rectangle. It is also defined as a parallelogram with four right angles, and a square is both a rectangle and a diamond.

Extended data:

1, the perimeter of the rectangle = (length+width) ×2. 2. The circumference of a square = side length ×4. 3. Area of a square = side length × side length. 4. Area of triangle = base × height ÷2. 5. The area of parallelogram = base × height. 6. Trapezoidal area = (upper bottom+lower bottom) × height ÷2. 7. Diameter = radius ×2 radius = diameter ÷2. 8.π× radius× 2. 9. Area of circle = π× radius× radius. Method of judging rectangle: 1. A parallelogram with right angles is a rectangle. 2. Parallelograms with equal diagonals are rectangles. 3. A parallelogram with adjacent sides perpendicular to each other is a rectangle. A quadrilateral with three right angles is a rectangle. 5. Quadrilaterals with equal diagonals and bisecting each other are rectangles. 6. (Through the parallelogram) ① In the parallelogram, ABCD: ∠ bad = 90 or BD=AC ∴ parallelogram ABCD is a rectangle.

Other common graphic formulas

Circumference = π× diameter = 2×π× radius

(Key) lateral area of the cylinder: the lateral area of the cylinder is equal to the perimeter of the bottom multiplied by the height.

(Key) Surface area of cylinder: Surface area of cylinder = side area of bottom area.

Volume formula

1. cuboid volume = length× width× height; 2. The volume of the cube = side length × side length × side length; 3. (Key) Volume of the cylinder: The volume of the cylinder is equal to the bottom area multiplied by the height; 4. (Answer) Volume of cone = bottom area × height.