AMC 12 2008b Problem 18

A pyramid has a square base $ABCD$ and vertex $E$. The area of square $ABCD$ is $196$, and the areas of $\triangle ABE$ and $\triangle CDE$ are $105$ and $91$, respectively. What is the volume of the pyramid?

(Solution)

\textbf{(A)}\ 392 \textbf{(B)}\ 196\sqrt {6} \textbf{(C)}\ 392\sqrt {2} \textbf{(D)}\ 392\sqrt {3} \textbf{(E)}\ 784