论文部分内容阅读
5.1图形的对称、平移和旋转重点难点易混易错点剖析复习重点:“图形的变化”这部分知识在近5年的河南中考中每年必考,且常设置2~4道题。分值为6~19分,在选择题、填空题和解答题中均有涉及,难度较大.常考点有:(1)图形的平移、折叠与旋转.(2)对称图形的识别.(3)图形折叠、平移、旋转的综合运用.复习难点:(1)折叠问题实际上是轴对称问题,折叠前后的图形关于折痕成轴对称,两图形全等.折叠图形中常会出现相似三角形,求解过程中常用勾股
5.1 The symmetry, translation and rotation of the key points Difficult and easy to analyze the misleading points: “Changes in the graphics ” This part of the knowledge in the past 5 years in Henan senior high school entrance examination will be required every year, and often set 2 to 4 questions. Points of 6 to 19 points in the multiple-choice questions, fill in the blank questions and answer questions are involved, the more difficult. Often test points are: (1) graphics translation, folding and rotation. (2) Symmetrical graphics recognition. (1) The folding problem is actually an axisymmetric problem, the graphics before and after folding are symmetrical about the crease, the two graphics are congruent, the similar triangle often appears in the folded graphics, Commonly used Pythagorean solve the process