A line is tangent to a circle at the point (2, 5). A parallel line is tangent to the circle at (9, 12). What is the common slope of the two lines? Express your answer as a common fraction.
+2666 Note that 2 lines form the diameter that is perpendicular to the slope of the line.
The slope of the line is \({7 \over 7} = 1 \), meaning the slope of the line is \(\color{brown}\boxed{-1}\)
