The slope of the line is determined by the change in #y# over the change in #x#.
#(Deltay)/(Deltax)#
#m=(y_2-y_1)/(x_2-x_1)#
Using the points (2,6) and (-3,-4)
#x_1=2#
#y_1=6#
#x_2=-3#
#y_2=-4#
#m = (6-(-4))/((-3)-2)#
#m = (6+4)/(-3-2)#
#m = (10)/(-5)#
#m=-2#