Question

From a point on the ground, 20 m away from the foot of a vertical tower, the angle elevation of the top of the tower is 60°, What is the height of the tower?

Answer 1

Let AB be the height of tower is h meters. 

Given that: angle of elevation is 60° and `BC=20` meters.

Here we have to find height of tower.

So we use trigonometric ratios.

In a triangle `ABC`, 

`⇒ tan C=(AB)/(BC)`

`⇒ tan 60°=h/20 [∵ tan 60°=sqrt3]`

`⇒ sqrt 3=h/20`

`⇒ h= 20sqrt3`

Hence height of tower is `20sqrt3`