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> A plane flies in a direction NW at an airspeed of $141$ km/hr. If the wind at the plane's cruise altitude is blowing with a speed of $100$ km/hr directly from the north, what is the plane's actual speed and direction relative to the ground?
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So I'm presuming you can do this with vectors. One of them pointing to the northwest, with a magnitude of 141 and one of them pointing to the south with a magnitude of 100. But how can I get the answer?