Question 198840
Note: *[Tex \LARGE \left(x_{1}, y_{1}\right)] is the first point *[Tex \LARGE \left(4,5\right)] and *[Tex \LARGE \left(x_{2}, y_{2}\right)] is the second point *[Tex \LARGE \left(4,4\right)].



{{{m=(y[2]-y[1])/(x[2]-x[1])}}} Start with the slope formula.



{{{m=(4-5)/(4-4)}}} Plug in {{{y[2]=4}}}, {{{y[1]=5}}}, {{{x[2]=4}}}, and {{{x[1]=4}}}



{{{m=(-1)/(4-4)}}} Subtract {{{5}}} from {{{4}}} to get {{{-1}}}



{{{m=(-1)/(0)}}} Subtract {{{4}}} from {{{4}}} to get {{{0}}}



Remember, you <b>cannot</b> divide by zero. So this means that the slope is undefined.