Question

What is the slope of a line perpendicular to `x-5y=10`?

Answer 1

The slope of the perpendicular line is the negative reciprocal, `-1/m`.

The slope of the original line is `-(A/B)=-(1/(-5))=1/5`

The slope of the perpendicular line is ...

`-1/m=-1/((1)/(5))=-1*5/1=-5/1=-5.`