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三角形相似 PowerPoint PPT Presentation


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三角形相似. 要点、考点聚焦 课前热身 典型例题解析 课时训练. 要点、考点聚焦. 1.本课时的重点是相似三角形的判定和性质. 2.相似三角形的定义:对应角相等,对应边成比例的三角形. 3.相似三角形的判定定理及其推论 判定定理1:两角对应相等的两个三角形相似. 判定定理2:两边对应成比例且夹角相等,两个三角形相似. 判定定理3:三边对应成比例的两个三角形相似 判定定理4:如果一个直角三角形的斜边和一条直角边与另一个直角三角形的斜边和一条直角边对应成比例,那么这两个直角三角形相似. 推论:直角三角形被斜边上的高分成的两个直角三角形 和原三角形相似.

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三角形相似

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