Question

How do you find the value of r such the points (9,r), (6,3) with slope m=-1/3?

Answer 1

`r=2`

Explanation:

Given two points (a,b) and (c,d) solve by formula `(d-b)/(c-a)=m`
therefore (9,r) and (6,3) solve to `(3-r)/(6-9)=-1/3`
where `3-r=1` since `6-9=-3`
finding r is `3-1=2`