The line MN joins the points M(2,10) and N(5,1). What is the equation of a line perpendicular to MN which also passes through point N?

Question

 I know I have to do the point slop form, however got a weird answer every time I used that equation.

Answer 1

slope (not slop) of MN = (10 - 1) / (2 - 5)

slope MN = 9 / -3

slope MN = -3

 

slope of perpendicular is 1/3

 

10 = (1/3)(2) + b

10 =2/3 + b

28/3 = b

 

equation of perpendicular through M:

 

y = x/3 - 28/3