In the figure below, $WXYZ$ is a rectangle with $WX=9$ and $WZ=27$. Point $M$ lies on $\overline{XY}$, and point $A$ lies on $\overline{YZ}$. If $\angle WMA$ is a right angle and the areas of $△WXM$ and $△WAZ$ are equal, what is the area of $△WMA$?