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Mon 10 Aug, 2020 06:44 pm
An airplane flies from city A to city B a distance of 150 miles and then turns through an angle of 40 degrees and heads towards city c.
As well as through what angle should the pilot turn at city C to return to city A? If the distance between cities a and c is 300 miles how far is it from city B to city C?
I figured out that the distance between town B and C is 169 miles.
Using the Law of Sines, I did the following to find the angle through which the pilot should turn at city C to return to city A
sine 140/300 = sin C/150
0.642 / 300 ≈ sin C / 150
0.00214 ≈ sin C / 150
0.321 ≈ sin C
18.72 ≈ C
The book's answer is
161.3° ≈ C
What am I doing wrong here?
Thanks....
@blueridge,
Look at your answer and the book's answer. Notice that they add up to 180? Both angles have the same sine value, so you have to make a picture to make sure you pick the right one.
@engineer,
After playing with this problem again, I figured out that the turn angle is 180° - C.
So, 180° - 18.72° = 161.28°, which become 161.3° after rounding to the nearest tenths.
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