Area is a geometric concept used to describe the space occupied by a figure on a plane. In the first section of Unit 5, Book 3, Beijing Normal University Press, we will learn more about what area is and how to calculate the area of a graph.
First of all, what is the area?
In life, we often come into contact with objects of various shapes, such as desks, blackboards, floors and so on. These objects all have a common feature, that is, they all have their own size, that is, the area they occupy. Area is an index used to measure the size of plane graphics, which can be expressed by numbers.
Second, the area of the rectangle.
First of all, we need to know the simplest figure-the area calculation method of rectangle. A rectangle has two groups of parallel sides, and the length of each group is a and b respectively. We can calculate the area of a rectangle by the following formula: area = length× width, that is, s = a× B. Where s stands for area, A stands for length and B stands for width.
Third, the area of the square.
A square is a special rectangle, its four sides are equal, and the length of each side is S. Similar to a rectangle, the area of a square is calculated by the square of the side length: area = side length × side length, that is, S = s× s.
Fourth, the area of the triangle.
Triangle is another common figure, which has three sides and three vertices. Calculating the area of a triangle is a little more complicated, which requires determinant calculation method. If it is known that the base length of a triangle is b and the height is h, then the area of this triangle can be calculated by the following formula: area =0.5× base length× height, that is, S = 0.5× b× h.
Verb (abbreviation of verb) abstract
By studying the area lesson word by word, I have a deeper understanding of the concept of area and learned how to calculate the area of rectangle, square and triangle. Area is a very important concept in geometry, which is widely used in daily life and study. Only by mastering the calculation method of area can we better understand and apply this concept and solve practical problems.