(轴对称图形的性质.ppt

N M B C A C’ A’ M B N B C A Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 对称轴 AB=CD，BE=CE ∠B=∠C 1. 如果两个图形关于某条直线对称，那么对应点所连的线段被 垂直平分。 2. 下图是轴对称图形，相等的线段是 ，相等的角 。 A B C D E Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 3．两个图形关于某直线对称，对称点一定 ( ) A．这直线的两旁 B．这直线的同旁 C．这直线上 D．这直线两旁或这直线上 D Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 4．轴对称图形沿对称轴对折后，对称轴两旁的部分（ ） A．完全重合 B．不完全重合 C．两者都有 A Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 轴对称图形的性质 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 轴对称图形 把一个图形沿着某条直线对折，直线两旁的部分能够完全重合，那么这个图形叫做轴对称图形 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 成轴对称 两个图形沿着某条直线对折，如果直线两旁的部分能够互相重合，那么，我们就说这两个图形关于这条直线成轴对称。 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 全等图形 两个能够完全重合的图形称为全等图形 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 1、轴对称图形和轴对称的区别 (1)轴对称图形是指一个具有特殊形状的图形, 只对一个图形而言; (2)对称轴不一定只有只有一条 (1)轴对称是指两个图形 的位置关系,必须涉及两个图形; (2)只有一条对称轴 轴对称图形 轴对称 区别 图 形 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 想一想 我们所学过的哪些几何图形是轴对称图形？ 线段、角、等腰三角形、长方形、正方形、菱形、圆、椭圆等 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. C的对称点是 ____的对称点是E D A的对称点是 能重合的点叫_________ 对称点 m F B 补充知识 Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. 经过线段中点并且垂直于这条线段的直线，叫做这