A line is tangent to a circle at the point (2, 5). A parallel line is tangent to the circle at (8, 13). What is the common slope of the two lines? Express your answer as a common fraction.
Ok, here I go:
To find the slope, we use our trusty formula- \(\frac{y_2-y_1}{x_2-x_1}\)
Plugging in the values, we have:\(\frac{13-5}{8-2}=\frac{8}{6}=\frac{4}{3}\)
But since the two tangents lines are perpendicular to this diameter and have a slope equal to the negative reciprocal of the diameter’s slope, we have \(\boxed{\frac{-3}{4}}\)