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Question
The angles of elevation of the top of a tower from two points at a distance of 4 m and 9 m from the base of the tower and in the same straight line with it are 60° and 30° respectively. Find the height of the tower.
Solution
Let the height of the tower be h m.
In ∆ABP,
`tan60^@ = h/4`
`=>sqrt3=h/4`
⇒h=1.73×4=6.92 cm
In ∆ABQ
`tan30^@=h/9`
`=>1/sqrt3=h/9`
`=>h=9/sqrt3cm= 5.20 cm`
Using the given data, we are getting two different values of h, which is not possible.
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Based on the above information, answer the following questions.
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- If ∠YAQ = 30°, then ∠AQD is also 30°, Why?
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OR
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