The topic of this problem is nodal analysis.

The problem is to determine the nodal equations for each node in the circuit.

Whenever we're doing nodal analysis,

we always start with identifying the nodes in the circuit, and we know that we

have a node at the upper left-hand side of the circuit, we'll call it node 1.

We have a node at the upper-right hand side of the circuit,

we'll call it node two.

We also have a ground node at the bottom,

which we know is at zero volts associated with the circuit.

So we have node one, node two, and the ground node at 0 volts.

So we're going to use nodal analysis and

Kirchhoff's current law to write the equations about node one and node two.

Ultimately, what we get from nodal analysis is the nodal voltages.

So we'll find through our series of equations, the delta voltage for

node one and the nodal voltage for node two.