初一年级数学用坐标表示平移主讲人王芳北京市第一七一中学一、复习回顾一.什么叫做平移?复习回顾A1C1B1A2C2B2ACB一.什么叫做平移?复习回顾A1C1B1A2C2B2ACB二.平移的性质有哪些?A1C1B1A2C2B2ACB复习回顾二.平移的性质有哪些?A1C1B1ACB复习回顾二、探索新知探究活动1.点的平移(2,1)AA1Oyx-11236457-2-3-412346789-1-2-35-410(6,1)(2,1)AOyx-11236457-2-3-412346789-1-2-35-410yx向右平移4个单位横坐标加4(6,1)A1A2(9,1)(2,1)AOyx-11236457-2-3-412346789-1-2-35-410(2,1)AOyx-11236457-2-3-412346789-1-2-35-410yx向右平移7个单位横坐标加7A2(9,1)(2,1)AOyx-11236457-2-3-412346789-1-2-35-410yx横坐标加4(6,1)A1向右平移4个单位(2,1)AOyx-11236457-2-3-412346789-1-2-35-410yx横坐标加7A2(9,1)向右平移7个单位(5,4)B1(-2,4)BOyx-11236457-2-3-412346789-1-2-35-410Oyx-11236457-2-3-412346789-1-2-35-410(5,4)B1(-2,4)B向右平移7个单位横坐标加7Oyx-11236457-2-3-412346789-1-2-35-410(5,4)B1(-2,4)B向右平移7个单位横坐标加7(2,1)A横坐标加4(6,1)A1向右平移4个单位A1(-5,1)A(2,1)Oyx-11236457-2-3-412346789-1-2-35-410-5Oyx-11236457-2-3-412346789-1-2-35-410-5向左平移7个单位A(2,1)A1(-5,1)横坐标减7Oyx-11236457-2-3-412346789-1-2-35-410-5(-2,4)B(-5,4)B1(-5,4)横坐标减3B1Oyx-11236457-2-3-412346789-1-2-35-410-5(-2,4)B向左平移7个单位(-5,4)Oyx-11236457-2-3-412346789-1-2-35-410-5A(2,1)A1(-5,1)横坐标减7(-2,4)BB1横坐标减3向左平移3个单位(-5,4)Oyx-11236457-2-3-412346789-1-2-35-410-5A(2,1)A1(-5,1)横坐标减7(-2,4)BB1横坐标减3(5,4)B1横坐标加7横坐标加4(6,1)A1xyO(x-a,y)(x+a,y)向左平移a个单位横坐标加a(x,y)向右平移a个单位横坐标减a探索平面直角坐标系中点的平移A1(2,1)(2,6)AOyx-11236457-2-3-412346789-1-2-35-410-5(2,1)向上平移5个单位纵坐标加5Oyx-11236457-2-3-412346789-1-2-35-410-5A1(2,6)AOyx-11236457-2-3-412346789-1-2-35-410-5(2,-4)A2(2,1)A(2,1)(2,-4)向下平移5个单位纵坐标减5A2AOyx-11236457-2-3-412346789-1-2-35-410-5(2,1)向上平移5个单位纵坐标加5A(2,-4)向下平移5个单位纵坐标减5A2A1(2,6)Oyx-11236457-2-3-412346789-1-2-35-410-5(x,y+b)(x,y-b)xyO向下平移b个单位纵坐标加b向...