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I'm looking to work out the current at I in the following circuit using Kirchoff's current law and nodal analysis:

[PLAIN]http://img853.imageshack.us/img853/4792/circuitgem.jpg [Broken]

Using Kirchoff's voltage law (and loop analysis), I got a current of (35/22)A, but for the current law method I'm having problems.

I obtained the following equations using Kirchoff's current law:

4i_{1}+2i_{2}+4i_{3}=5

-4i_{3}-2i_{4}=-10

and nodal analysis:

-i_{2}+i_{3}-i_{4}=0

i_{1}+i_{4}=I

But solving these 4 equations produces a value for I of 0, which doesn't make sense, let alone agree with the answer using the other method.

Any help will be greatly appreciated.

Thank you

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# Homework Help: Kirchhoff's current law and nodal analysis

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