Respuesta :
If the plane is flying at an altitude of 21,000 feet, it is perpendicular to the observer's horizontal line of sight. Thus, I concluded that the given information be assigned to the attachment below.
Given -
( Observer at point O, plane flying at point P
( Plane at 55° angle to horizontal line of sight, altitude of 21,000 feet
The distance ( x ), is represented by the line segment OP, with which we have to determine the length of. Therefore we can conclude the following -
[tex]Sin( 55 ) = Altitude / Distance,\\Sin( 55 ) = 21,000 / x,\\----------------\\x = \frac{21,000}{Sin( 55 )},\\x = 21,000 / 0.81915204428\\\\x = ( About ) 25636 feet\\[/tex]
As you can see, the distance from the plane to the observer is about 25,636 ft!
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Answer:
25,636 feet
Step-by-step explanation:
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