Question

a flag staff of 5 m high stands on a building of 25 m height for an observer at a height of 30 m the flag staff & the building subtend equal angle the distance of the observer from the top of the flag staff is​

Answer 1

Answer:

ANSWER

In △DBC

tanα=

x

5

.......(i)

and In △DAC

tan2α=

x

30

⇒

1−tan

2

α

2tanα

=

x

30

⇒

1−

x

2

25

2

x

5

=

x

30

⇒

x

2

−25

10x

=

x

30

⇒10x

2

=30x

2

−750

⇒20x

2

=750

⇒x

2

=

2

75

⇒x=5

2

3

m

solution