<PRE><B>Question 144643</B>
Two boats leave a marina at the same time. Boat A travels at 20km/hr in a direction of 65 degrees. Boat B travels at 12.5km/hr in a direction of 145 degrees. How far apart are the boats after 2 hours. (2) In what direction would the skipper of Boat A have to look to see Boat B. I have this.
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I think you have the right idea here:
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Boat A 20km x 2 hrs = 40 km
Boat B 12.5 km x 2 hrs = 25 km.
However the angle should be
They are offset by an angle of 145-65 = 80 degrees.
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Using the Law of Cosines you should get:
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x^2 = 40^2 + 25^2 - 2(40)(25)cos(80 degrees) = 1877.70 so x = 43.33. 
The boats are 43.33 km apart after 2 hours.
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Draw a diagram of this and you will see that Skipper A would have to look south-west to see boat B</PRE>