A line cannot be perpendicular to two points. It can be perpendicular to the segment joining two points or to the line or line segment that passes through the two points.
First find the slope of the line that passes through the two points using the slope formula:
where and are the coordinates of the given points.
Then calculate the negative reciprocal, , to find the slope of a perpendicular.
John
My calculator said it, I believe it, that settles it
