Answer:
Step-by-step explanation:
( [tex]x_{1}[/tex] , [tex]y_{1}[/tex] )
( [tex]x_{2}[/tex] , [tex]y_{2}[/tex] )
m = [tex]\frac{y_{2} -y_{1} }{x_{2} -x_{1} }[/tex]
~~~~~~~~~~~~
( - 9 , - 3 )
( 1 , - 3 )
m = [tex]\frac{-3+(-3)}{-9-1}[/tex] = [tex]\frac{0}{-10}[/tex] = 0 , line is horizontal
