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1、Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.图1图2图3图4托盘天平托盘砝码镊子指针Evaluation only.Evaluation only. Created with Aspo
2、se.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.如果在天平的两端放上不同的物 体,你能用式子表示出两边物体质量 间的关系吗? 想一想:Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Clie
3、nt Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.自学提示自学课本P5354,完成以下目标: 1、观察图1、图2,你能得到什么信息?2、分别用一个式子表示出图3、图4中 天平两端的质量关系。3、什么叫方程?Evaluation only.Evaluation only. Created with Aspose.Slides for .NET
4、3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.空杯子重100g平衡100g100g图1Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Sli
5、des for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.平衡100gEvaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Asp
6、ose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.100g一杯水有多重?如果水重x克,杯 子和水共重100+x图2Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose
7、 Pty Ltd.100+x100g100+x20050g100g100gEvaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.100g100g100g100+x100+x30050g100g1
8、00g100g图3Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.100g100g100g50g100+x图3Evaluation only.Evaluation only. Create
9、d with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.100g100g100g 50g100+x250100+x平衡图4Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Cli
10、ent Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.(2)100x 200(3)100x 200(3)100x 200(3)100x 200(3)100x 200(3)100x 300(4)100x = 250100x = 250像这样的含有未知数的等式,称为方程。(4)100x = 250比较这两个等 式有什么相同点和 不同点?Evalua
11、tion only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.小明也列了两了式子,不小心被墨水 弄脏了。猜猜他原来列的是不是方程?(1) 6X + =78 (2) 36 + =42 猜一猜:Evaluation o
12、nly.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.判断下面式子哪些是方程,是的打“ ”, 不是的打“ ” 。 35+65=100 ( ) -14 72 ( ) y+24 ( ) 5 +32=47 ( ) 28 16
13、+14 ( ) 3=1.5 ( ) 做一做:X X XXEvaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.一个方程必须具备的条件: 1、是等式。 2、含有未知数。二者缺一不可想一想:要想判断
14、一个式子是不是方程 你认为必须具备哪些条件?Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.它们也是方程吗?说说理由。 (1) 3 +2 =15 ( ) (2)6(a+2)=42 ( )
15、(3)2 +3y=70 ( )Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.下面式子哪些是等式,哪些是方程? 36+X40 3824 X7.80 453X2 8.4y 8X1.6等式有:( ) 方程有:( ) 找一找:Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyrigh