求一道英语数学题

来源：百度知道 编辑：UC知道 时间：2024/06/14 07:39:38
david walks along a straight road. At one point he notices a tower on a bearing of 053° with an angle of elevation of 21°, After walking 230m, the tower is on bearing of 342°,with an angle of elevation of 26°, find the height of the tower correct to the nearest metre

跟据题意画出草图你会发现其实就是一个一条楞垂直于底面的三楞椎图我不画了作三楞锥OABC其中OB垂直于面ABC底边AC=230,角BAC=18,角BCA=53,角OAB=26,角OCB=21.然后设塔高OB=h,因为三角形垂直关系有AB=h.ctg26,BC=h.ctg21然后三角形ABC中AC=AB.sin18+BC.sin53=230然后解方程就可以了