Answer
not perpendicular
Work Step by Step
m=$\frac{y_2-y_1}{x_2-x_1}$
m=$\frac{-6-9}{-1-2}$
m=$\frac{-15}{-3}$
m=5
m=$\frac{y_2-y_1}{x_2-x_1}$
m=$\frac{-1-3}{-15-5}$
m=$\frac{-4}{-20}$
m=$\frac{1}{5}$
5$\times$$\frac{1}{5}$$\ne$-1
Therefore the lines are not perpendicular.