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## Homework Statement

Calculate the current through the resistor of resistance for circuit B.

Express your answer in terms of EMF, R1, and R2.

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## Homework Equations

Kirchhoff's Loop and junction rules

## The Attempt at a Solution

So I have these equations that I've figured out using Kirchhoff's Rules:

There are two loops:

EMF = I1R1 + I3R2

EMF = I2R1 + I3R2

I1 + I2 = I3

I figured out pretty quickly that I1 = I2 by subtracting the top from the middle equation. I'm just not sure what to do next really...

The answer I'm supposed to get to is I3 = (2EMF) / (R1 +2R2)

I don't know why this is so confusing...but it is. So, assuming I did everything right, how do I get to the last (final) equation for I3?

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