[tex]\bf (\stackrel{x_1}{8}~,~\stackrel{y_1}{h})\qquad (\stackrel{x_2}{5}~,~\stackrel{y_2}{-8}) \\\\\\ slope = m\implies \cfrac{\stackrel{rise}{ y_2- y_1}}{\stackrel{run}{ x_2- x_1}}\implies \cfrac{-8-h}{5-8}=6\implies \cfrac{-8-h}{-3}=6 \\\\\\ -8-h=-18\implies -8+18=h\implies 10=h[/tex]
