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d was able to solve it in two methods but contrasting answers.

I first solved it by converting the two star connected networks into delta networks and further solving them.
Then I solved by considering one star, converted that to delta and then used parallel series concepts.
If anyone can tell me what's the correct approach I would appreciate the help.
Thanks!

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    \$\begingroup\$ Welcome to EE.SE. If you have tried something, please write every calculation you have done into your question not only some abstract ideas. Otherwise we cannot tell you where you are stuck. Hint: Redraw that circuit in "canonical" form. (I can solve it without pen, paper or calculator) \$\endgroup\$ – Ariser Apr 19 '20 at 5:37
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    \$\begingroup\$ They look like stars, don't they. But had you noticed that the 8 ohm is in parallel with the horizontal 4 ohm resistor (why do we use component designators?), and the vertical 4 ohm is in parallel with the 3 ohm? Does that make it easier? What result do you get now? \$\endgroup\$ – Neil_UK Apr 19 '20 at 5:37
  • \$\begingroup\$ Same suggestion here: show us the calculations you have done so far, even if it's a photo of what you did on paper! We want to see what have you done so far, if and where you got it wrong, and if you have invested more time and effort than what you expect from us to invest while helping you. \$\endgroup\$ – Edin Fifić Apr 19 '20 at 8:27
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You have been trying to solve it the complicated way before trying the simple way.
The key thing is to first carefully observe it.
Then you will notice that the 4Ω and 3Ω (R2 and R3 in my schematic) are in parallel, as well as the 8Ω and the other 4Ω (R5 and R6), and that R2, R3, R5 and R6 are connected all together at one end.

schematic

simulate this circuit – Schematic created using CircuitLab

schematic

simulate this circuit

schematic

simulate this circuit

Then you notice that R1 is in series with the R2/R3 combination, just like R4 is in series with the R5/R6 combination, and the obvious fact that R1 and R4 are connected together at the "A" point:

schematic

simulate this circuit

Now you calculate the parallel resistance of R2 and R3, and the parallel resistance of R5 and R6.
Then you calculate the series resistance of the R1 branch which is R1 in series with the calculated R2/R3 parallel combination, and do the same with the R4 branch.
Finally, you calculate the parallel resistances of those 2 branches.
See how easy that was? No need for stars and deltas.

Think in simple terms first, and then use the more complex terms when you realize the simple terms can't work.
Again, the key is to carefully observe first. There is no shame in taking a little more time in the beginning just to see the whole picture, as that will save you from the headaches, problems, incorrect solutions, and the waste of even more time down the road.

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