2000 Gauss 7 Problem 19

The diagram shows two isosceles right-triangles with sides as marked. What is the area of the shaded region?

\textbf{(A)}\ 4.5 \text{ cm}^2\quad \textbf{(B)}\ 8 \text{ cm}^2\quad \textbf{(C)}\ 12.5 \text{ cm}^2\quad \textbf{(D)}\ 16 \text{ cm}^2\quad \textbf{(E)}\ 17 \text{ cm}^2

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

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