How do you find the value of r such the points (6,2), (9,r) with slope m=-1?

1 Answer
Apr 21, 2017

r=-1

Explanation:

First, write the equation of the line using point slope form using (6,2) and m=-1. Point slope form is y-y_1=m(x-x_1):

y-2=-1(x-6)

Distribute the -1:

y-2=-x+6

Now solve for y:

y=-x+8

Now plug in (9,r):

r=-9+8

Solve for r:

r=-1