solve for the variable r in terms of the other variables, p, q, and s.?

Question

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http://img516.imageshack.us/img516/9867/18430669cx8.gif

Answer 1

p = (3s - r)/(rq)

First, multiply both sides by rq:

prq = 3s - r

Next, add r to both sides:

prq + r = 3s

Use the distributive property:

r(pq + 1) = 3s

Divide both sides by pq + 1:

r = 3s/(pq+1)

And we are done.