Question

A tower stands on a horizontal plane and surmounted by vertical flagstaff of height h. At a point on the plane, the angles of elevation of the bottom and the top of the flagstaff are A and B respectively, find the height of the tower ? Please answer guys​

Answer 1

Answer:

Step-by-step explanation:Let height be y ΔOAC

tanθ=  

B

P

​  

 

tanβ=  

OA

CA

​  

 

tanβ=  

x

y+h

​  

            (y+h)→ Let AB, AB+BC

Let OA→ x

x=[  

tanβ

y+x

​  

]

Consider ΔOAB

tanα=  

x

y

​  

=  

Base

perpendicular

​  

 

x=  

tanα

y

​  

 

tanα

y

​  

=  

tanβ

y+h

​  

 

ytanβ=tanαy+tanαh

ytanβ−tany=tanαh

y(tanβ−tanα)=tanαh

y=  

tanβ−tanα

htanα

​