一次函数图象信息题中,有一类相遇或追击的“双线图”问题,由于这类问题的情境比较复杂,图象信息丰富,许多学生在解答这类问题时,感觉十分棘手.下面举例说明此类问题的求解方法.例1甲、乙两地之间有一条笔直的公路l,小明从甲地出发沿公路l步行前往乙地,同时小亮从乙地出发沿公路l骑自行车前往甲地,小亮到达甲地停留一段时间,原路原速返回,追上小明后两人一起步行到乙地.设小明 There is a class of “double-line graph” problems encountered or pursued in the image function of one-time function. Due to the complexity of the situation and the richness of image information, many students find it very difficult to solve such problems. The following example illustrates the solution to such problems: Example 1 A, B There is a straight road between the two l, Xiao Ming, starting from a road along the highway l walk to B, at the same time small light starting from the road l ride along the road l A bicycle to a small light to reach a place to stay for some time, the original return of the original speed, catch up with two small walk together to the second floor.