(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The circuit is attached, i want to know what I4 is ( Answer 15mA ). Been working on this problem for 3h and i always end up when i try to multiply the invert matrix "A" with the matrix "B" then my calculator says "It´s not invertable"..

2. Relevant equations

Kirchoffs Laws

3. The attempt at a solution

junction equations = 2

loop equations = 4

1: I1+I2-I3=0

2: I1+I6-I5=0

a: R*I3-R*I4=6

b: -R*I1-R*I3=-12

c: R*I4+R*I6=6

d: R*I3+R*I6=12

Matrix A:

6x6

1 1 -1 0 0 0

1 0 0 0 -1 1

0 0 100 -100 0 0

-100 0 -100 0 0 0

0 0 0 -100 0 -100

0 0 100 0 0 100

Matrix B:

6x1

0

0

6

-12

6

12

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# Homework Help: Multi-loop circuit (kirchoffs laws)

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