Question

Find the slope of a line perpendicular to the line whose slope is infinite slope?

Answer 1

$$\begin{gathered} \mathrm{We}\mathrm{know}\mathrm{that}\mathrm{if}\mathrm{two}\mathrm{lines}\mathrm{having}\mathrm{slope}{\mathrm{m}}_1\mathrm{and}{\mathrm{m}}_2\mathrm{are}\mathrm{perpendicular}\mathrm{to}\mathrm{each}\mathrm{other}\mathrm{then}, \\ {\mathrm{m}}_1\times {\mathrm{m}}_2=-1 \\ \mathrm{Now}, \\ {\mathrm{m}}_1=\infty \\ \Rightarrow \infty \times {\mathrm{m}}_2=-1 \\ \Rightarrow {\mathrm{m}}_2=-\frac{1}{\infty }=0 \\ \Rightarrow {\mathbf{m}}_{\mathbf{2}}\mathbf{=}\mathbf{0} \end{gathered}$$