In the circuit given below, $R=18.$ Find the value of $V_1$ using nodal analysis.

The nodal equation when the $10$ and $5$ resistors are not combined is:

$\frac{(V_1-10)}{A}+\frac{B}{10}+\frac{(V_1-0)}{C}+\frac{D}{4}=0$

where $A=$

$,B=($ Click $to$ select $)vv,C=$

$,$ and D $=($Click to select$)vv.$

The value of $V_1$ in the circuit is V$.$