How To Construct Auxiliary Plane Geometry Graph Of Research And Practice In Junior High School

According to the questionnaire survey between junior high school students and teachers, the author finds that most teachers and students think it is hard for them to learn plane geometry well, and find the graph variability. They do not know how to make a start. How to design a good auxiliary graph is the main difficulty for them. Now in order to help them to solve this problem, the study "The research and practice about how to design a good auxiliary graph in studying the plane geometry for junior high school students" is mentioned in this paper.Several ways, the main results in this paper, to design three kinds of auxiliary graphs, which include auxiliary similar graphs, auxiliary polygon graph and auxiliary circle, are obtained. By an analysis of some examples, we can help the students to find out the conditional characteristic of the structure and then summarize the characteristics, finally find out a graphic formation process. Moreover, in this paper, the author will try her best to make all the characteristics universal and get a widely applicable conclusion, which is good for them to solve all this kind of questions by the same way.Two teaching examples in teaching practice are considered in this paper:Example No.1:the Proof of the Pythagorean Theorem; Example No.2:Design Similar triangles by Power of a point. According to the theoretical research and Experimental Learning, the author finds that it is really very important to make the students to grasp how to conclude the characteristics of the questions. Meanwhile we should guide them to analysis and classify the questions, then make them to choose the proper auxiliary graph which is correspondence to the questions. All this will extremely promote the students’ ability to design the auxiliary graph in plane geometry. Finally, Some suggestions about how to design an auxiliary graph are given:Make a good schedule of teaching; Pay attention to writing ability; Strength the relationship between unknown and known knowledge; Encourage the students to do research on graph by themselves, and found that the composition process.