previous question R=ab/a+b. Need to isolate the a. Question reads R equals to: a times b (on top) divided by a plus b

Question

Thanks

Answer 1

so, just follow the normal steps. No mystery here.

R(a+b) = ab
Ra+Rb = ab
a(R-b) = -Rb
a = Rb/(b-R)

or, note that
1/R = (a+b)/ab
1/R = 1/b + 1/a
1/a = 1/R - 1/b
1/a = (b-R)/Rb
a = Rb/(b-R)