Solving Current in a Circuit with Kirchhoff's Rules

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Homework Statement



The currents are flowing in the direction indicated by the arrows. A negative current denotes flow opposite to the direction of the arrow. Assume the batteries have zero internal resistance.

http://img123.imageshack.us/img123/2045/599c898aa10950d7027807dyc7.th.jpg

A) Find the current through the 14.4Ω resistor and the 8.6 V battery at the top of the circuit. Answer in units of A.
B) Find the current through the 23.2 Ω resistor in the center of the circuit. Answer in units of A.

Homework Equations


Kirchhoff's Junction and Loop Rules


The Attempt at a Solution




By applying the Kirchhoff's voltage law to the above loop I get
8.6V - (23.2Ω)I1 - (14.4Ω)I = 0

23.2I1 + 14.4I = 8.6 ........(1)

Applying the Kirchhoff's voltage law to the down loop I get

16.4V + (23.2Ω)I1 = 0

I1 = - 0.71A

Substitute this value in the eq(1)

8.6V + (23.2)(0.71) = 14.4I

I = 1.74A

Therefore the current passes through the battery 8.6V and the resistance 14.4Ω is 1.74A

For Part B, I thought that the current would be equal to I1 which I already solved for in Part A, so the current would be -0.71 A.

I've pretty much worked everything out but I was hoping if someone could tell me if I was doing it right or not. I'm not too confident when it comes to these problems. Any comments would be very helpful. Thanks!
 
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