✔ 最佳答案
Refer to the diagram,
where h m is the height of the tower, and x is the distance between the tower and the second point.
In the smaller right-angled triangle :
h/x = tan36°
x = h/tan36° …… [1]
In the greater right-angled triangle :
h / (x + 30) = tan27°
x + 30 = h/tan27°
x = (h/tan27°) + 30 …… [2]
[1] = [2] :
h/tan36° = (h/tan27°) - 30
(h/tan27°) - (h/tan36°) = 30
h [(1/tan27°) - (1/tan36°)] = 30
h = 30 / [(1/tan27°) - (1/tan36°)]
h = 51.2 (to 1 decimal point)
Height of the tower = 51.2 m