2006 Fermat Problem 15

The points (5,3) and (1,-1) are plotted on a sheet of graph paper. The sheet of graph paper is folded along a line so that the point (5,3) lands on top of the point (1,-1). The equation of the line that represents the fold is

\textbf{(A)}\ y=-x+1\quad \textbf{(B)}\ y=-x+2\quad \textbf{(C)}\ y=-x+3\quad \textbf{(D)}\ y=-x+4\quad \textbf{(E)}\ y=-x+5

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

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