2013 Cayley Problem 22

In the diagram, PQRS is a rectangle. Point T is outside the rectangle so that \triangle PTQ is an isosceles right-angled triangle with hypotenuse PQ. If PQ = 4 and QR = 3, then the area of \triangle PTR is

\textbf{(A)}\ 5\quad \textbf{(B)}\ 6\quad \textbf{(C)}\ 7\quad \textbf{(D)}\ 8\quad \textbf{(E)}\ 9

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

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