Question

Height of a building is 10 metres and there
is a point ‘P’ on the ground and a helicopter
is flying over the top of the building.
Angles of elevation of the top of the
building and the helicopter from point P
are respectively 30degrees and 60degrees. What is the
height of the helicopter from the ground ?
1.30 m
2.45 m
3.60m
4.70m

Answer 1

Answer:

30

Step-by-step explanation:

let the point P be at a distance x from the building

as angle of elevation is 30°

tan 30°=height of the building/x

1/√3= 10/x

x= 10√3

now let the height of helicopter is y

as angle of elevation=60°

tan 60 =√3=y/x

= y/10√3

y=10√3 × √3

=30m