[tex]\bf (\stackrel{x_1}{-1}~,~\stackrel{y_1}{-4})\qquad (\stackrel{x_2}{3}~,~\stackrel{y_2}{-4}) \\\\\\ slope = m\implies \cfrac{\stackrel{rise}{ y_2- y_1}}{\stackrel{run}{ x_2- x_1}}\implies \cfrac{-4-(-4)}{3-(-1)}\implies \cfrac{-4+4}{3+1}\implies \cfrac{0}{4}\implies 0 \\\\\\ \begin{array}{|c|ll} \cline{1-1} \textit{point-slope form}\\ \cline{1-1} \\ y-y_1=m(x-x_1) \\\\ \cline{1-1} \end{array}\implies y-(-4)=0[x-(-1)] \\\\\\ y+4=0(x+1)\implies y+4=0\implies \blacktriangleright y=-4 \blacktriangleleft[/tex]
