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Wed 13 Jul, 2005 05:08 am
An airplane traveling at an altitude of 2050 feet sights the top of a 50-foot tower at an angle of depression of 28 degrees from point A. After the airplane continues in level flight to point B, the angle of depression to the same tower is 34 degrees. Find, to the nearest foot, the distance that the plane has traveled from point A to point B.
I know that X = distance from point A to point B. This is what I need to find.
How can I use the law of sines to find X?
You use trig, not necessarily the law of sines.
Draw the situation on a piece of paper using right triangles. One leg of the triangle is the altitude of the airplan less the height of the tower (2050-50=2000 ft). This leg is opposite the measured angle of depression and is the same in both right triangles.
What is being determined is distance from the tower is the right triangle leg adjacent to the angle of depression. Now what trignometric function related opposite over adjacent legs of a right triangle-------------------------------------------
Tan right?
so at point A
Tan(28)=2000/D0 or D0=2000/Tan(28)
& at point B
Tan(34)=2000/D1 or D1=2000/Tan(34)
so the distance travelled is the difference between D0 and D1
Rap
ok
Good notes. I like comparing notes.
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