A 1.5 m tall boy is looking at the top of a temple which is 30 meter in height from a point at certain distance .The angle of elevation from his eye to the top of the crown of the temple increases from 30° to 60° as he walks towards the temple. Find the distance he walked towards the temple.

please give a solution ................


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Answers

2014-12-19T22:43:38+05:30
Height of boy 1.5m
Height of temple from ground 30m
Height of temple from boys vision= 30-1.5=28.5 m
Let distance between boy and temple be x.
using trigonometry we have tan 30°=28.5/x                                         
                                          ⇒  1/√3=28.5/x                                        
                                          ⇒    x=49.26         
     when the angle of elevation is
60° boy has walked distance =y
                                  we have tan60 = 28.5/(49.26-y)
                                             ⇒     √3 = 28.5/(49.26-y)
                                             ⇒  49.26-y=28.5/√3=16.45
                                                         y= 32.81
He has walked 32.81m toward temple.
 

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