Suppose the speed of the wind is $w$, the speed of the plane is $p$, and the ground speed is $g$. Let $A$ denote the angle you plane needs to make with the wind, and $B$ the angle that the wind makes with your desired direction of travel, as illustrated in this Figure:
{\bf For simplicity assume that the angles are measured in radians so that you can use the WeBWorK trig functions and their inverses without conversion.} Then
$A=$ .
Your answer will be a mathematical expression in $B$, $p$ and $w$.
Once you have the angle $A$ you can compute your ground speed using either the Law of Sines or the Law of Cosines.
Hint: Apply the Law of Sines to get the angle.