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The angle of elevation from a point on t...

The angle of elevation from a point on the bank of a river of the top of a temple on the other bank is `45^(@)`. Retreating 50 m, the observer finds the new angle of elevation as `30^(@)`. What is the width of the river?

A

50m

B

`50sqrt(3)`m

C

`50//(sqrt(3)-1)m`

D

100m

Text Solution

Verified by Experts

The correct Answer is:
C
In `DeltaABC, tan 45^(@)=(AB)/(BC)`

`rArr 1=(h)/(x)`
`rArr h = x " " ...(i)`
Now, in `DeltaABD`,
`rArr
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