图中有一个以“垂径定理”作后盾的图形,在历年的中考中屡屡出现,成为考查圆的知识不可或缺的的焦点,现以07年中考题为例作一归类,供同学们学习参考.基本图形图1中涉及四条与圆有关的重 In the picture, there is a graph backed by the vertical trail theorem. It has repeatedly appeared in the mid-term exams of the calendar year and has become an indispensable focus of the knowledge of the examination circle. Now the 2007 mid-term exam questions are used as an example. For students to learn to reference. The basic graphic Figure 1 involves four related to the weight of the circle