Answer:
r = S/2mh
Explanation:
In this equation, we want to isolate r.
To start, divide both sides by 2:
S/2 = 2mrh/2
The 2/2 cancels out on the right
S/2 = mrh
Now divide both sides by mh:
(S/2) / mh = mrh / mh
The mh/mh cancels out on the right
S/2mh = r
And now switch the sides for proper format:
r = S/2mh