Mathematics
From a window A, 10 m above the ground the angle of elevation of the top C of a tower is x°, where tan x° = and the angle of depression of the foot D of the tower is y°, where tan y° = . Calculate the height CD of the tower in metres.
Heights & Distances
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Answer
From figure,
⇒ AB = DE = 10 m.
In ∆AED
In ∆AEC,
From figure,
CD = DE + CE = 10 + 100 = 110 m.
Hence, height of tower (CD) = 110 m.
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