5(ii)
The angle of elevation of the top of a 100 m high tree from two points A and B on the opposite side of the tree are 52° and 45° respectively. Find the distance AB, to the nearest metre.

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From figure,
⇒ tan 52° = $\frac{CD}{AC}$
⇒ 1.28 = $\frac{100}{AC}$
⇒ AC = $\frac{100}{1.28}$ = 78.125 m
⇒ tan 45° = $\frac{CD}{BC}$
⇒ 1 = $\frac{100}{BC}$
⇒ BC = 100 m
⇒ AB = AC + BC = 78.125 + 100 = 178.125 m
Hence, AB = 178.125 m