Question

A boy who is 1.4m tall, sighted the top of a flag pole at an angle of elevation of 36°. if the boy is 9.5m away from the flag pole, calculate the height of the flag pole​

Answer 1

The height of flag pole=8.3m

Explanation:

We are given that

Height of boy=1.4 m

`\theta=36^(\circ)`

Distance of boy from the flag pole=9.5 m

We have to find the height of the flag pole​.

BCDE is a rectangle

BC=ED=1.4 m

CD=BE=9.5 m

In triangle ABE

`(AB)/(BE)=tan36^(\circ)`

Using the formula

`tan\theta=(Perpendicular\;side)/(base)`

`(AB)/(9.5)=tan 36^(\circ)`

`AB=9.5tan36^(\circ)`

AB=6.90 m

Height of flag pole=AB+BC=6.90+1.4

Height of flag pole=8.3m