And then we have one more current flowing into that node.

These are current flowing through the resistor R2 at the top of the circuit.

That resistance is between node 1 and node 2.

So if we're looking at the current flowing into node 1 through resistor R2.

It's V2 minus V1 divided by R2,

V2- V1 divided by R2.

And that's equal to 0, that's our last current flowing into node 1.

So that's our first independent equation.

We have a second equation that we can write around node 2.

And again, summing the currents into node 2.

We know that we have I sub A flowing into node 2,

it's on the right hand side of the circuit.

And then we have the currents which are flowing through R3 and

R2 into node 2 as well.

So looking at R2 first, we have the current flowing left to right.

So it's going to be V1 minus V2 divided by R2.

V1 minus V2 divided by R2 and we have one other current

the current flowing up through R3 flowing into node 2.

So that's going to be our ground nodes,

0 volts- the nodal voltage at that second V2, divided by R sub 3.

And that's all of our currents flowing into node 2.

So that's sum is going to be equal to 0.

So now we have two independent equation.

And as we can see, we have the two equations that we have three unknowns,

we have V1 and V2 for the nodal voltages and

we also have I sub 0 which is in there as well and

I sub 0 comes from our dependent source, it's beta I sub 0.

So again, we need that third equation which relates our controlling

parameter I sub 0 to our nodal voltages and so we have to think about

that third equation for our set of three equations and our three unknowns.

So how do we make that relationship?

We see that I sub 0 is flowing down through R3 and