Look at the picture.
[tex]m=\dfrac{\Delta y}{\Delta x}[/tex]
[tex]105)\\not\ exist\\\\106)\\m=\dfrac{2}{3}\\\\107)\\m=\dfrac{5}{-1}=-5\\\\108)\\m=\dfrac{-1}{8}=-\dfrac{1}{8}\\\\109)\\m=\dfrac{7}{3}[/tex]