对一道中考数学综合题的分析及反思

• 作 者: 赵星
• 机 构: 南京市溧水区第二初级中学,
• 出 处: 数理化学习(初中版)
• 发表日期: 2015年01期

原题呈现对于两个相似三角形,如果沿周界按对应点顺序环绕的方向相同,那么称这两个三角形互为顺相似;如果沿周界按对应点顺序环绕的方向相反,那么称这两个三角形互为逆相似.例如,如图1,△ABC∽△A’B’C’,且沿周界ABCA与A’B’C’A’环绕的方向相同,因此△ABC与△A’B’C’互为顺相似;如图2,△ABC∽△A’B’C’,且沿周界ABCA与A B C A环绕的方向相

The original title is presented to two similar triangles, and if the directions are the same in the order of the corresponding points along the perimeter, the two triangles are said to be similar to each other; if the directions are reversed in the order of the corresponding points along the perimeter, then both For example, as shown in Figure 1, △ ABC ∽ △ A’B’C ’, and along the perimeter ABCA and A’B’C’A’ around the same direction, so △ ABC and △ A ’ B’C ’is similar to each other; as shown in Figure 2, △ ABC∽ △ A’B’C’, and along the perimeter ABCA and ABCA surrounded by the direction