an airplane flies due north at a speed of 200 m/sec. A west wind blows at 20.0 m/sec. what is the resultant velocity of the airplane?

Refer to the figure below.

Magnitude of the resultant velocity (speed)
= √(200² + 20²) m/sec
= 201 m/sec

tanθ = 20/200
θ = tan⁻¹(20/200) = 5.71°
Direction of the resultant velocity = N 5.71° E

Velocity seen from ground Vsfg = √
200^2+20^2 =  20√
10^2+1 = 201 m/sec NE 
heading angle = arctan Va/Vw = arctan 200/20 = 84.29° NoE  or 5.71° EoN 

Get out your E6-B whizwheel and figure it out yourself.  If you have to hide behind chickenshit anonymity for a question like this I'm not going to do the homework for you.