Question Number 174190 by Best1 last updated on 26/Jul/22
Answered by MikeH last updated on 26/Jul/22
$$\left(\mathrm{19}\right)\:−{x}+\mathrm{2}{y}−\mathrm{1}=\mathrm{0} \\ $$$$\Rightarrow{d}\:=\:\mid\frac{−\left(\mathrm{2}\right)+\mathrm{2}\left(\mathrm{1}\right)−\mathrm{1}}{\:\sqrt{\left(−\mathrm{1}\right)^{\mathrm{2}} +\left(\mathrm{2}\right)^{\mathrm{2}} }}\mid\:=\:\frac{\mathrm{1}}{\:\sqrt{\mathrm{5}}}\:=\:\frac{\sqrt{\mathrm{5}}}{\mathrm{5}} \\ $$