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A person on the top of a tall building looks through his binoculars at his friend that is 300 ft away from the building on the ground. If the angle of depression from the person on the building is 30°, how tall is the building?

User Randhir Yadav
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1 Answer

22 votes
22 votes

Answer:

520 feets

Explanation:

The height of the building, h can be obtuined using trigonometry ;

From the attached diagram, opposite side = 300 feets ; height, h = adjacent side

Hence,

Tan θ = opposite / Adjacent

Tan 30° = 300 / height

0.5773502 = 300 / height

Height = 300 / 0.5773502

Height = 519.615

Height = 520 feets

A person on the top of a tall building looks through his binoculars at his friend-example-1
User Gjergj
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