Plane rectangular coordinate system is the content of mathematics in the second volume of grade seven. Outline requirements: understand the meaning of plane rectangular coordinate system and master the coordinate characteristics of each quadrant point skillfully; Master the coordinate solution of some special points. This chapter shares some difficulties to help you improve your learning efficiency.
On the plane, two vertical axes with a common origin form a plane rectangular coordinate system. The coordinate system divides the whole plane into four parts, which are called the first quadrant, the second quadrant, the third quadrant and the fourth quadrant. The first quadrant: both abscissa and ordinate are greater than zero; The second quadrant: the abscissa is less than zero and the ordinate is greater than zero;
The third quadrant: both abscissa and ordinate are less than zero; The fourth quadrant: the abscissa is greater than zero and the ordinate is less than zero. In the plane rectangular coordinate system, the ordinate of the point on the X axis is 0, and the abscissa of the point on the Y axis is 0; If the abscissas of two points are the same, the line segment or straight line connecting the two points is parallel to the Y axis; If the vertical coordinates of two points are the same, the line segment connecting the two points is parallel to the X axis.
The meaning of learning:
1, cognitive self. Knowledge is infinite, so is learning. The more knowledge you learn, the more ignorant you will find yourself. A lot of knowledge is unclear or even unheard of.
2. Improve yourself. In the development of modern society, achievement is not the only way out, but learning is what we want to pursue all our lives.
3. broaden your horizons. Read thousands of books and take Wan Li Road. Learning can add interest to our plain life. Even if you can't take Wan Li Road, you can study thousands of books.
4. satisfy the thirst for knowledge. Everyone has the right to pursue knowledge and the right to choose whether to study. Some people know themselves by learning. Some people improve themselves through learning. Some people broaden their horizons through study.
5. Create more possibilities. The road to learning is difficult, but it is substantial.