Question

boy 1.7 m tall is standing on a horizontal ground, 50m away from a building. The

angle of elevation of the top of the building from his eye is 60° . Calculate the height of the

building (Take √3 = 1.73)​

Answer 1

Answer:

87m

Step-by-step explanation:

Use SOH CAH TOA

then assign height as opposite

use TAN as opposite= x and adjscent = 50m

tan(60)= OPP/ADJ

tan(60)=x/50

x = tan(60) x 50

x = 86.6m

x= 87m

Answer 2

Answer:

   The height of building is 88.3 m

Step-by-step explanation:

• In context to the question, we have to find the height of the building

given,

height of the boy = 1.7m

as per the figure,

height of the building = x + height of the boy ( as the boy is standing on ground)

angle of elevation (θ) = 60°

In Δ ADE,

tan θ = $\frac{DE}{AD}$

tan θ = $\frac{x}{50}$

tan 60° = $\frac{x}{50}$

√3 = $\frac{x}{50}$

x = 50√3 m

As we know,

height of the building = x + height of the boy

height of the building = 50√3 + 1.7

height of the building = 50 √3 +1.7     [ √3 = 1.732]

height of the building = 86.6 + 1.7  

height of the building = 88.3m

Therefore, height of building is 88.3 m