What is the slope of any line perpendicular to the line passing through #(4,2)# and #(-1,10)#?
First figure out the slope of the line that passes through those points using the slope formula:
NOTE: You could also let
Which leads to the same answer (thanks Tony B.!):
Perpendicular lines always have different signed slopes (meaning if one line's slope is positive, the perpendicular line's slope is negative and similarly negative
Also perpendicular lines are reciprocals of each other so our new slope is: