Answer: Choice D. 3 : r=3
Explanation:
Easiest method and probably only method given the graph without knowing exact points besides an asymptote at x=-3.
Since we know there is an asymptote at x=-3, we just solve for the denominator and find r, when x=-3.
We are setting equation equal to 0, because when the denominator is 0, the graph has an asymptote at that point.
x+r=0
-3+r=0
r=3