(Hopefully) Quick Question: How to turn 1/R to R?

Question

The whole problem is this:

 

           1  =  1  +  1 

Solve   R      R₁       R₂     for R

 

Basically, I'm pretty sure that the first thing I need to do is make 1/R just R... right? The thing is, I have to show my work and I'm not really sure if I'm even headed in the right direction. I know I can't do 1/R•R/1 because that would just cancel to 1. Please help me... I'm really confused >.<

 

 

Answer 1

1/R = 1/R₁ + 1/R₂

 

Multiply both sides by the LCD, RR₁R_2.

 

We obtain:  R₁R₂ = RR₂ + RR₁

 

                 R₁R₂ = R(R₂ + R₁)

 

                    R = (R₁R₂)/(R₁+ R₂)