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1、3.1图形的平移第二课时成都市通锦中学李芳123456780–1–2–3–4–512349105在直角坐标系中描出以下各点：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)并用线段依次连接，看一看是什么图案。yx123456780–1–2–3–4–512349105图中的鱼是将坐标为：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的点用线段依次连接而成的则坐标变化为纵坐标保持不变，将各坐标的横坐标加２又会怎样？yx原图形被横向（向右）平移2个单位(x,y)(0,0)(5,4)(3,0)(5,
2、1)(5,-1)(3,0)(4,-2)(0,0)(x+2,y)(2,0)(7,4)(5,0)(7,1)(7,-1)(5,0)(6,-2)(2,0)123456780–1–2–3–4–512349105图中的鱼是将坐标为：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的点用线段依次连接而成的则坐标变化为：纵坐标保持不变，将各坐标的横坐标减２，图案会变成什么样？yx-1-2原图形被向左平移2个单位(x,y)(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)(x-2,y)(-２,0)(3,4)(1,
3、0)(3,1)(3,-1)(1,0)(2,-2)(-2,0)123456780–1–2–3–4–512345图中的鱼是将坐标为：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的点用线段依次连接而成的横坐标保持不变，将各坐标的纵坐标都减１，则原图型变为什么样？yx原图形被向下平移1个单位123456780–1–2–3–4–512345图中的鱼是将坐标为：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的点用线段依次连接而成的横坐标保持不变，将各坐标的纵坐标都加２，则原图型变为什么样？yx原图形
4、被纵向（向上）平移2个单位平移变换1.纵坐标不变，横坐标分别增加（减少）a个单位时，图形平移a个单位；2.横坐标不变，纵坐标分别增加（减少）a个单位时，图形平移a个单位；向右（向左）向上（向下）123456780–1–2–3–4–512349105在直角坐标系中描出以下各点：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)并用线段依次连接,看一看是什么图案.yx图中的鱼是将坐标为：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的点用线段依次连接而成的纵坐标保持不变，将各坐标的横坐标变成原来的
5、２倍会得到什么？则坐标变化为：原图形被横向拉伸2倍(x,y)(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)(2x,y)(0,0)(10,4)(6,0)(10,1)(10,-1)(6,0)(8,-2)(0,0)123456780–1–2–3–4–512349105图中的鱼是将坐标为：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的点用线段依次连接而成的纵坐标保持不变,将各坐标的横坐标变成原来的1/2，图形会怎么变？则坐标变化为：yx原图形被横向压缩1/2(x,y)(0,0)(5,4)(3,0
6、)(5,1)(5,-1)(3,0)(4,-2)(0,0)(x/2,y)(0,0)(2.5,4)(1.5,0)(2.5,1)(2.5,-1)(1.5,0)(2,-2)(0,0)–4123456780–1–2–36123457910xy图中的鱼是将坐标为：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的点用线段依次连接而成的如果横坐标保持不变，纵坐标变成原来的½，那么所得图案又会发生什么变化?原图形被纵向压缩1/2–4123456780–1–2–36123457910xy图中的鱼是将坐标为：(0,0)(5,4)(3,0)(5,1)
7、(5,-1)(3,0)(4,-2)(0,0)的点用线段依次连接而成的如果横坐标保持不变，纵坐标变成原来的２倍，那么所得图案又会发生什么变化?原图形被纵向拉伸２倍–4123456780–1–2–361234578910xy1.图中的鱼是将坐标为：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的点用线段依次连接而成的如果横坐标与纵坐标同时乘以２，那么所得图案又会发生什么变化?原坐标变为：原图形被横向、纵向各拉伸2倍原图形的形状没变，面积是原来的4倍。(x,y)(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2
8、)(0,0
