A man observes the angle of elevation of the top of a building to be 30° . He walks towards it in a horizontal line through its base . On covering 60m the angle of elevation changes to 60°. Find the height of the building correct to the nearest metre.
Answers
★ Solution
Let the height be :- h
Let the distance between B and C be :- x
In ∆BCD ,
h/x = tan 60°
→ h/x = √3
→ h = √3 × x
In ∆ ACD,
h/(x+60) = tan 30°
➡ h/(x+60) = 1/√3
➡ h√3 = x + 60
➡ 3x - x = 60
➡ 2x = 60
➡ x = 30
Now,
h = √3 x
➡ h = √3 × 30
➡ h = 30√3
➡ h = 30 × 1.732
➡ h = 51.96 m
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Answer ⭐
The height is 51.96 m
Answer:
Notice⭐
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⠀⠀⠀⠀⠀⠀⠀from 8:00 a.m. to 12:00 a.m.
⠀⠀ School assembly hall, St Xavier's School
All the students are requested to participate in this competition as it will be one of the most exciting one.
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\huge\mathfrak{Notes}Notes
Format :-
✍ Catchy headline
✍ Topic of the notice
✍ Date
✍ Time
✍ Place / venue of the event
this is answer for your upper question