The fifth chapter is the intersection line and parallel line. This chapter is very important and must be tested in the exam. Especially the concept part is as important as the square root and cube root of real numbers introduced in Chapter 6 of the proof part. Usually, it is relatively simple to choose the plane rectangular coordinate system in chapter 7 in the fill-in-the-blank questions, but we also need to remember the binary linear method in chapter 8 carefully. ...