Is it possible to find current through a branch or to find a voltage across a branch by using wye delta or delta wye connections?

Yes, it is possible to find the current through a branch or the voltage across a branch using wye-delta (Y-Δ) or delta-wye (Δ-Y) transformations in circuit analysis. These transformations allow you to convert between equivalent configurations of resistors, which can simplify the analysis of complex circuits. Once the circuit is simplified, standard techniques such as Ohm's law and Kirchhoff's laws can be applied to determine the desired current or voltage.