Question

Two poles stand on either side of a road. At the point midway between the two
posts, the angles of inclination(elevation) of their tops are 30° and 60°. Find the
length of the shorter posts if the longer post is of 15m long.​

Answer 1

In △AOC,

tan60

o

=

x

h

∴x=

3

h

In △BOD,

tan30

o

=

100−x

h

3

1

=

100−x

h

100−x=h

3

100−h

3

=x x=

3

h

∴100−h

3

=

3

h

∴h=25

3

m

∴x=

3

h

=

3

25

3

∴x=25 m

∴OC=25 m and OD=75 m.