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Question
A kite is attached to a string. Find the length of the string, when the height of the kite is 60 m and the string makes an angle 30° with the ground.
Solution 1
Let the length of the rope be x m
`sin 30^circ = 60/x `
`=> 1/2 = 60/x`
∴ x = 120 m
So the length of the rope is 120 m
Solution 2
`tan 30^circ = (AB)/(BC)`
`1/sqrt(3) = 60/(BC)`
`BC = 60sqrt(3)`
`AC = sqrt((AB)^2 + (BC)^2`
= `sqrt((60)^2 + (60sqrt(3))^2`
= `60 sqrt(1 + (sqrt(3))^2`
= 60 × 2
AC = 120 m
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