document.write( "Question 258923: An airbus A320 aircraft is cruising at an altitude of 10000 m. The aircraft is flying in a straight line away from Rachel, who is standing on the ground. If she sees the angle of elevation of the aircraft change from 70 degrees to 33 degrees in one minute, what is its cruising speed, to the nearest kilometer per hour? \n" ); document.write( "
Algebra.Com's Answer #264819 by rfadrogane(214)\"\" \"About 
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An airbus A320 aircraft is cruising at an altitude of 10000 m. The aircraft is flying in a straight line away from Rachel, who is standing on the ground. If she sees the angle of elevation of the aircraft change from 70 degrees to 33 degrees in one minute, what is its cruising speed, to the nearest kilometer per hour?
\n" ); document.write( "Sol'n:
\n" ); document.write( "let x1= Initial horizontal distance at 70 deg. from observer
\n" ); document.write( " x2= Final horizontal distance at 33 deg. from observer
\n" ); document.write( " v = velocity
\n" ); document.write( "x1 = 10,000 cot 70 deg.= 3,639.702-m
\n" ); document.write( "x2 = 10,000 cot 33 deg. = 15,398.65-m\r
\n" ); document.write( "\n" ); document.write( "so, the horizontal distance travel in one minute is x2-x1
\n" ); document.write( "d = 15,398.65-3,639.702 = 11,758.948-m
\n" ); document.write( "then, the velocity (v):\r
\n" ); document.write( "\n" ); document.write( "v = d/t
\n" ); document.write( "v = 11,758.948/60 sec.
\n" ); document.write( "v = 195.98 m/s
\n" ); document.write( "v = 195.98 m/s x 3600 s/hr x 1 km/1,000 m
\n" ); document.write( "v = 705.54 kph say 706 kph - answer \n" ); document.write( "
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