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Question
A kit is flying at a height of 75 metres from the ground level, attached to a string inclined at 60 to the horizontal. Find the length of the string to the nearest metre.
Solution
Let AC be the string of length, hm and C be the point, makes an angle of 60° and the kite is flying at the height of 75 m from the ground level.
In a triangle, ABC, given that height of kite is AB = 75 m and angle C = 60°
Now we have to find the length of the string.
So we use trigonometric ratios.
In a triangle ABC
`=> sin C = (AB)/(AC)`
`=> sin 60^@ = 75/h`
`=> sqrt3/2 = 75/h`
`=> h = 150/sqrt3`
Therefore h = 86.6
Hence length of string is 87 meters
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