Question

A cessna plane flies with a speed of 150km/h relative to the air and points due east. A wind is blowing at a speed of 20km/h at 45 degrees south of east (ie the wind is blowing from the northwest). The resultant veloity of the plane relative to the ground is?

Answer 1

It is the vector sum of the wind velocity vector and the velocity of the plane with respect to the air.

You should be able to perform this operation yourself