If the line is perpendicular to the line joining the points and

MATHEMATICS · Single correct · A Level · Mathematics · Coordinate geometry in the (x y) plane · Coordinate geometry in the (x y) plane

Problem

If the line

4x+3y+k=0

is perpendicular to the line joining the points

(2,-5)

and

(k,1)

, then the value of

k

is (a)

-6

(b)

6.5

(c)

10

(d)

-2.5