SOLUTION: A ship sails in the direction S 70 degrees W for 3 hours at 50km/h . It then changes direction to travel a bearing of 120 degrees for 4 hours at the same speed. Show with a diagram
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-> SOLUTION: A ship sails in the direction S 70 degrees W for 3 hours at 50km/h . It then changes direction to travel a bearing of 120 degrees for 4 hours at the same speed. Show with a diagram
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Question 1118829: A ship sails in the direction S 70 degrees W for 3 hours at 50km/h . It then changes direction to travel a bearing of 120 degrees for 4 hours at the same speed. Show with a diagram.
a) After 7 hours, how far is the ship from its original position? Express your answer to the nearest whole kilometer.
b)To the nearest degree, what is the bearing of the final position of the ship from the original position?
Thank you
The turn from 70 west of south to bearing 120 is 130 degrees, hence Angle OAB is 50 degrees. 3 hours at 50 km/hr is 150 km, and 4 hours at 50 km/hr is 200 km. With two sides and the included angle, use the Law of Cosines to calculate the measure of Segment OB, the current ship's displacement from the origin.
Then use the Law of Sines to calculate Angle AOB. Subtract 70 degrees from Angle AOB, then subtract that difference from 180 degrees to obtain the final bearing.
John
My calculator said it, I believe it, that settles it
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