A balloon is directly above one end of a bridge. The angle of depression of the other end of the bridge from the balloon is `48^(@)`. If the height of the balloon above the bridge is 122 m, then what is the length of the bridge ?

Options

A. `122 sin 48^(@) m`
B. `122 tan 42^(@) m`
C. `122 cos 48^(@) m`
D. `122 tan 48^(@)m`

Answer

A

Explanation

Let the bridge is BC and height above the bridge AB=122m.

From DABC,
`cot 48^(@)=(BC)/(AB)=(BC)/(122)`
`BC=122. cot (48^(@))`
`=122.cot ( 90^(@)-42^(@))`
`=122. tan 42^(@)`