SOLUTION: solve formula for the indicated variable. I=E/R+r for R

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Question 18999: solve formula for the indicated variable.
I=E/R+r for R

Answer by Earlsdon(6103) About Me  (Show Source):
You can put this solution on YOUR website!
Ohm's law for the amount of current (I) in a cicuit having (R+r) ohms of resistance with an applied voltage of E volts.
I+=+E%2F%28R%2Br%29 Solve for R, multiply both sides by (R+r).
I%28R%2Br%29+=+E Expand (distributive property) the left side.
IR+%2B+Ir+=+E Subtract Ir from both sides.
IR+=+E+-+Ir Finally divide both sides by I.
R+=+%28E+-+Ir%29%2FI