## Elementary Geometry for College Students (6th Edition)

$-4$
We use the equation for slope: $m = \frac{y_2-y_1}{x_2-x_1}$ $m_1 = \frac{3-1}{11-3}=\frac{1}{4}$ The opposite reciprocal of this is -4, so this is the slope of the perpendicular bisector.