Question

An airplane pilot over the Pacific sights an atoll at an angle of depression of 5° At this time, the horizontal distance from the airplane to the atoll is 4629 meters. What is the height of the plane to the nearest meter?

Answer 1

Answer:  405 meters (choice B)

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Explanation:

The angle adjacent to the 5 degree angle is 90-5 = 85 degrees

Or you could note that 85+5 = 90.

Then from here you'd use the tangent ratio

tan(angle) = opposite/adjacent

tan(85) = 4629/x

x*tan(85) = 4629

x = 4629/tan(85)

x = 404.985 approximately

x = 405 meters when rounding to the nearest whole number.