Basic Vector Question
A plane flies at 800km/h and wishes to travel to a city 800km, due east. There is a 80km/h wind from the northeast. a) What should the planes heading be? b) How long will the trip take?
I've solved a) by drawing out a Vector Diagram and using sine law. The plane needs to head S86°E. Part me is holding me up. I have to figure out the speed of the plane in order to get the time. I have the distance which is 800, so I just need to divide by the speed. To do that, I simply use cosine law and get 854.6km/h. And 800km divide by 854km/h gives me 0.9hours or 54 minutes. However the correct answer is actually 1hour and 5 min. Any ideas? (http://imgur.com/a/02Ixt)

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