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Question
When an observer at a distance of 12 m from a tree looks at the top of the tree, the angle of elevation is 60°. What is the height of the tree? `(sqrt 3 = 1.73)`
Solution
tan 60° = `"AB"/"BC"`
`sqrt 3 = "h"/12`
`therefore "h" = 12 sqrt 3` m
= 12 × 1.73 m
h = 20.76 m
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