1, the perimeter represents the total length of the rectangle, the "length" represents the length of the long side of the rectangle, and the "width" represents the length of the short side of the rectangle. For example, a rectangle with a length of 10cm and a width of 5cm can be calculated according to the above formula: circumference = 2× (10+5) = 2×15 = 30cm. Therefore, the circumference of this rectangle is 30 cm.
2. It should be noted that when calculating the perimeter of a rectangle, the values of length and width need to be substituted into the formula for calculation. At the same time, because a rectangle has two equal long sides and two equal wide sides, it needs to be multiplied by 2 when calculating the perimeter.
Knowledge about rectangles
1, a rectangle is a common geometric shape, defined as having a parallelogram, in which the diagonal divides the quadrilateral into two congruent triangles.
2. Rectangles are common in daily life, such as doors and windows, books and computer screens. Rectangles also often appear in various architectural designs, such as windows and doorframes of buildings.
3. Rectangles are not only common in architecture and design, but also often used in mathematics. For example, in geometry, rectangle is a basic figure, which can be used to learn and study various geometric theorems and properties. In algebra, rectangles can be used to solve some equations and inequalities.
4, the nature of the rectangle, the opposite sides are equal: the opposite sides of the rectangle are equal, that is, the length and width are equal. All four corners are right angles: all four corners of a rectangle are right angles, that is, 90 degrees. Diagonal equality: the diagonals of rectangles are equal, that is, the length of their diagonals is equal. This is a parallelogram: a rectangle is a parallelogram with all the attributes of a parallelogram.
In real life, rectangles are also widely used. For example, rectangle is one of the basic shapes when making furniture. Rectangles are also widely used to make electronic products, such as mobile phones, tablets and televisions.