A rectangle is a parallelogram with right angles, which is called a rectangle. It is also defined as a parallelogram with four right angles, and a square is both a rectangle and a diamond.

The essence of a rectangle is: two diagonal lines are equal; Two diagonal lines are equally divided; Two groups of opposite sides are parallel respectively; The two groups of opposite sides are equal respectively; All four corners are right angles; There are two symmetrical axes (there are four squares); Unstable (easily deformed); The square of the diagonal length of a rectangle is the sum of the squares of both sides; The quadrilateral obtained by connecting the midpoints of the sides of the rectangle in turn is a diamond.

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Practical methods of primary school mathematics;

1, Primary School Mathematics Learning Method-Understanding Memory Method

Mathematical knowledge is ever-changing, so you can't memorize it by rote. Therefore, in teaching, teachers should fully mobilize the enthusiasm of students' thinking and let students remember on the basis of understanding. Like what is a trapezoid? First, through careful observation, let students understand the meaning of "only one set of opposing faces" and what will happen if the word "only" is removed.

Through positive thinking, students realize that "only one group of edges is parallel" means that two opposite sides of four edges are a group, one of which is parallel and the other is not parallel. It is easy for students to remember the concept of trapezoid on the basis of understanding.

2. Primary school mathematics learning method-regular memory method.

Mathematical knowledge is regular, so long as students are guided to master it, they can effectively remember it. For example: memory length, area, floor area ratio unit. Because the propulsion rate between adjacent units in length is 10, the propulsion rate between adjacent units in area is 100, and the propulsion rate between adjacent units in volume is 1000. It's easier to remember when you master this rule.

3. Primary school mathematics learning method-image memory method.

Primary school students' thinking is mainly visual. For example, in a year-long series of cognitive teaching, children are asked to memorize numbers with some physical images: compare "2" to ducklings and "3" to ears. This will awaken children's concrete sense of abstract numbers.

Of course, the choice of learning methods cannot be fixed, and it must vary from person to person. According to the age characteristics of students, the difficulty of teaching content and the design of teaching methods should also have different emphasis.

One-to-one online tutoring of Jiafu Education guides students' mathematics learning methods, and strives to combine changing ideas with teaching methods, after class, teacher guidance with students' exploration, and establish a crisscross learning method guidance network to promote students to master correct learning methods.