How Do You Apply Kirchhoff's Rules to Solve for Currents in a Complex Circuit?

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Homework Statement


Using Kirchhoff's rules, find the currents I1, I2, and I3 in the circuit shown where R1 = 8.0 ohms, R2 = 9.0 ohms, and R3 = 5.0 ohms.
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Homework Equations


Loop law, Junction law

The Attempt at a Solution


I know how to work the formulas, but the picture is really confusing. The directions of the currents don't make any sense. I have arrows going away from both the positive and negative terminal and I can't figure out how to set up the equations with the arrows like that.
 

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The first thing you need to do is choose a direction which you will take as positive, either clockwise or anti-clockwise. Once you have chosen your convention make sure you stick to it. Then just start applying Kirchoff's laws to the loops and junctions taking care to stick to the convention you defined at the start.