Question

Find the slope of the lines that are (a) parallel lines (b) perpendicular lines to the lines passing through the pair of points (3, 4)(2,-1)

Answer 1

Find the slope of the line joining your two given points (you should know how to do that)

A line parallel will have the same slope

A line perpendicular will have a slope which is the negative reciprocal of the given slope

let me know what you get

Answer 2

Slope is 5
Parallel is 5 or 1/5
Perpendicular is -5

Answer 3

your slope of the given line is correct as 5

Then a parallel line also has a slope of 5

a perpendicular line will have slope of -1/5

your statement of
"Parallel is 5 or 1/5" is illogical.

same for " perpendicular is -5" , makes no sense to me.
Perpendicular is a property, -5 is a quantity
That is like saying " funny is -5"

Answer 4

find the slopes of lines (i) parallel to and (ii) perpendicular to the line joining (6,3),(-4,5).