近年来出现了许多以全等为载体的情景应用题.此类题目密切联系实际,贴近学生的生活.给出的问题往往不是纯数学的形态,而是给出一种情景,一种实际需求,要求解决一个现实问题.它重在考查学生的数学素养,激发学生的求知欲.一、确定撑开后折叠椅的宽度例1某大学计划为新生配备如图1所示的折叠椅.图2是折叠椅撑开后的侧面示意图,其中椅腿AB和CD的长相等,O是它们的中点.撑开后的折 In recent years, there have been many situation application questions based on congruent, which are closely related to the reality and close to the life of the students.The questions given are often not purely mathematical, but given a scenario and an actual demand , To solve a real problem.It focuses on examining students ’mathematical literacy, to stimulate students’ thirst for knowledge.First, to determine the width of the folding chair after stretching Example 1 A university plans to equip the freshmen with a folding chair as shown in Figure 1. Figure 2 is a side plan view of the folding chair after it has been opened, wherein the length of the legs AB and CD are equal and O is their midpoint.