ANSWER:
75.8 miles per hour, 83.3°
Explanation:
Given:
Plane velocity is 350 mi/hr N70E° (90 - 70 = 20°)
Ground velocity is 390 mi/hr, 30°
The ground velocity is the magnitude V + W, just like this:
We know that for V it would be:
Therefore:
We calculate the magnitude using the norm of the vector, like this:
The speed of wind is 75.8 miles per hour
We calculate the direction of the angle as follows:
The direction angle of the wind is 83.3°