Question

the angle of elevation of the top of a tower at a point on the ground is 30°if on walking 20m toward the angle of elevation become 60°,then the height of the tower is​

Answer 1

Answer:

Given 

Let BC=x

⟹AC=20+x 

From ΔBCD 

tan60=xCD 

CD=3x⋯(1)

From ΔACD 

tan30=x+20CD 

CD=31(x+20)⋯(2)

From (1)&(2) 

⟹3x=31(x+20) 

⟹3x=x+20 

⟹2x=20 

⟹x=10 

From (1) 

Height of tower is 3x 

⟹103