2012 Fermat Problem 5

In the diagram, PQRS is a square and M is the midpoint of PQ. The area of triangle MQR is 100. The area of the square PQRS is

\textbf{(A)}\ 200\quad \textbf{(B)}\ 500\quad \textbf{(C)}\ 300\quad \textbf{(D)}\ 400\quad \textbf{(E)}\ 800

If there are no answer choices shown, enter a numerical answer.

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