2000 Gauss 7 Problem 17

ABCD is a square that is made up of two identical rectangles and two squares of area 4 \text{cm}^2 and 16 \text{cm}^2. What is the area, in \text{cm}^2, of the square ABCD?

\textbf{(A)}\ 64\quad \textbf{(B)}\ 49\quad \textbf{(C)}\ 25\quad \textbf{(D)}\ 36\quad \textbf{(E)}\ 20

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

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