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在人教版八年级数学上册,有一道习题(习题12.2,第46页,第8题):如图,分别作出△PQR关于直线m和直线n对称的图形.它们的对应点的坐标之间分别有什么关系?解析本题是教科书“12.2.2用坐标表示轴对称”的课后习题,教科书中已经探索了关于坐标轴对称的点的坐标规律:点(x,y)关于x轴对称的点的坐标为(x,-y);点(x,y)关于y轴对称的点的坐标为(-x,y).本题可以利用教材中探索关于坐标轴对称的点的坐标变化的方法来解决.先作出轴对称图形,写出对称点的坐标,再归纳总结得出规律:点(x,y)关于直线m对称的点的坐标为(-x+2,y);点(x,y)关于直线n
In the eighth edition of the PEP, there is an exercise (Exercise 12.2, Page 46, Problem 8): As shown in the figure, the PQR is plotted symmetrically about the line m and the line n. The coordinates of their corresponding points What is the relationship? Analyze this question is the textbook “12.2.2 coordinate axisymmetric ” after-school exercise, the textbook has been explored on the coordinate axis of the coordinate point of the law: point (x, y) on the x-axis (X, y); (x, y) The coordinates of the points symmetrical about the y-axis are (-x, y). This question can be used to explore the coordinate changes of coordinates The first axisymmetric graphics, write the coordinates of the symmetry point, and then concluded that the law concluded: point (x, y) on the symmetry of the line m point coordinates (-x +2, y); point (x, y) about a straight line n