Vectors in Space · Hard problem

Vectors $\mathbf u$ and $\mathbf v$ satisfy $\lVert\mathbf u\rVert^2 = 25$, $\lVert\mathbf v\rVert^2 = 16$, and $\mathbf u\cdot\mathbf v = -12$. Find the area of the parallelogram spanned by $\mathbf u$ and $\mathbf v$.