[tex]\bf (\stackrel{x_1}{-3}~,~\stackrel{y_1}{0})\qquad(\stackrel{x_2}{0}~,~\stackrel{y_2}{0})\\\\\\ slope = m\implies\cfrac{\stackrel{rise}{ y_2- y_1}}{\stackrel{run}{ x_2- x_1}}\implies \cfrac{0-0}{0-(-3)}\implies \cfrac{0-0}{0+3}\implies \cfrac{0}{3}\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-0=0[x-(-3)]\\\\\\y=0(x+3)\implies \blacktriangleright y=0 \blacktriangleleft[/tex]