Understanding how to re-draw circuits

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Homework Statement



I need to find I1,I2,I3,Va,Vb but i don't even know to read the circuit. i know how to to do series circuits and parallel circuits but not this. How do i read this circuit and know which ones are in parallel or in series. is there a way to re-draw it? I have the solution and answer. Therefore i don't need the step by step solution since i already have it,is just that it doesn't explain why they did it that why.
These are the I1=4A ,I2=1.33, I3=.67, I4=2.67,va=8.0,and vb i don't know.
Please help understanding what is going on in this circuit.
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I would work my way up from the bottom, simplifying bits and pieces as I go. R5 and R3 are in parallel, right? So you could combine those two resistors into a single resistance. Keep chipping away at it until you have a single loop.
 
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If you combine circuit elements you will lose that components individual voltage and/or current.

I reccoend doing a KCL at Va and Va. Then solve for Va and Vb, and the currents will be easy to find.
 
Mark44 said:
I would work my way up from the bottom, simplifying bits and pieces as I go. R5 and R3 are in parallel, right? So you could combine those two resistors into a single resistance. Keep chipping away at it until you have a single loop.
if i do ((R5||R3)+R2)||R4 and this would be in series with R1 right? now to get Vb i think i would do Vb=R5(I2-I3) but what if that R5 was not there then how would i solve for vb
 
Lopez said:
if i do ((R5||R3)+R2)||R4 and this would be in series with R1 right? now to get Vb i think i would do Vb=R5(I2-I3) but what if that R5 was not there then how would i solve for vb
If R5 was not there then I2 and I3 would change. you cannot solve for an unknown value with unknown values