# Mirror, Mirror

Geometry Level 3

The point $$P(5, 3)$$ was reflected over a line in the $$x,y$$ plane. Its resulting position was $$P'$$ at $$(-3, 9)$$. The line it was reflected over can be written in standard form as $$Ax + By = C$$ where $$A, B$$, and $$C$$ are integers with no common factors, and $$A$$ is a positive integer. $$Find A + B + C$$.

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