Convert the Y in the given circuit to $\Delta$, redraw the whole circuit with the $\Delta$, then draw the
simplified circuits. Solve for the current I, the voltage drop across 21$\Omega$ resistor, and the power of
the voltage source, and the power dissipated by-21$\Omega$ resistor.
$R_1 = 18 \Omega$
6$\Omega$
6$\Omega$
60 V
6$\Omega$
18$\Omega$
21 $\Omega$
