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

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To solve for currents I1, I2, and I3 using Kirchhoff's rules, first establish a consistent direction for current flow, either clockwise or anti-clockwise. This chosen direction will guide the application of Kirchhoff's loop and junction laws. It's essential to maintain this convention throughout the calculations to avoid confusion. After setting the direction, apply the laws systematically to the circuit's loops and junctions. Following these steps will help clarify the relationships between the currents and resolve the circuit's complexities.
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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.
 
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