I came up with three equations, to find three different currents in a DC circuit, using Kirchhoff's loop rule, but when I solved them as a matrix in my calculator the bottom row becomes all zero's and the first two rows do not appear to be in "rref" form. I solved the system of equations by hand and when I add the solution from the first two (my new equation) to the third I get 0=0. Is this because they are dependent? If I use Kirchoffs junction rule to get an additional equation I can substitute the junction equation for any of the original three and get the answers. Should I always use the junction rule to find at least one of my equations, and is this problem due to not having used an equation from the junction rule originally or is it an occasional occurance and normally using any three equations (following Kirchhoff's rules) will give me the results I need?(adsbygoogle = window.adsbygoogle || []).push({});

thanks for the help.

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# Homework Help: Kirchhoff's Rules, system of equation problem

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