Chapter 2 Linear Equations and Functions - 2.2 Find Slope and Rate of Change - Guided Practice for Example 4 - Page 85: 11

perpendicular

By using the slope formula, the slopes of the lines are: $m_1=\frac{y_2-y_1}{x_2-x_1}=\frac{8-(-4)}{-2-2}=\frac{12}{-4}=-3.$ $m_2=\frac{y_2-y_1}{x_2-x_1}=\frac{1-2}{-5-(-2)}=\frac{-1}{-3}=\frac{1}{3}.$ Since $m_1m_2=-1$, they are perpendicular.