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Question
In the following figure, what are the angles of depression from the observing position O1 and O2of the object at A?
Solution
In a triangle, `o1 AC`
`⇒ ∠ A=180°-(90°+60°)`
`⇒ ∠ A=180°-150°` We know that `[ ∠A+ ∠B ∠C=180 °]`
`⇒ ∠ A=30°` '
Again,
In a triangle `o2 AB,`
⇒ `∠ o_2=180°-(90°+45°)`
⇒`∠ o_2=180°-135°`
⇒ `∠ o_2=45°`
Hence the required angles are` 30° 45°`.
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Based on the above information, answer the following questions.
- What is the measure of ∠APD?
- If ∠YAQ = 30°, then ∠AQD is also 30°, Why?
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OR
Find length of DQ
