Find I_1 in the network.

Image from: Irwin, J. David., and R. M. Nelms. Basic Engineering Circuit Analysis, Tenth Edition. N.p.: John Wiley & Sons, 2010.

#### Solution:

### We will write Kirchhoff’s current law for nodes A and B (which were arbitrarily chosen). (Forgot Kirchhoff’s current law?)

### Node B:

### I_2=6+4

### (here, we assigned I_2 as the current coming into the node)

### I_2=10mA

### Node A:

### I_1+I_2=20

### I_1=20-I_2

### I_1=20-10

### I_1=10mA

###### This question can be found in Basic Engineering Circuit Analysis, 10th edition, chapter 2, question 2.10.