Answer:
r = 10
Step-by-step explanation:
You want to find r such that ...
-20 = 60/-6 -r
r = 60/-6 +20 . . . . . add 20+r
r = -10 +20 = 10
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If you mean h(x) = 60/(x -r), then the answer is different.
-20 = 60/(-6-r)
-6-r = 60/-20 . . . . . multiply by (-6-r)/(-20)
-r = -3 +6 = 3 . . . . . add 6, simplify
r = -3 . . . . . . . . . . . . multiply by -1