Finding currents and voltages in a ladder network with Kirchhoff's laws

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vaio911
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Homework Statement



Find [itex]i_1,i_2,v_A,\text{ and }v_H[/itex] in the ladder network. Calculate the power dissipated in the [itex]2\;\Omega[/itex] resistor.

http://i.snag.gy/PIhxl.jpg


Homework Equations



Kirchhoff's Laws (i.e. current law, voltage law).


The Attempt at a Solution



Ok, I know that I can simplify the circuit down to one loop then use Ohm's law to calculate [itex]i_1[/itex], but then I have to do other things to get the other stuff.

I tried to make a system to solve this problem using the laws.
Can somebody tell me where I'm doing wrong here?

[itex] \begin{align}<br /> i_b&=i_c+i_a\\<br /> i_c&=i_e+i_d\\<br /> i_e&=i_g+i_f\\<br /> 12i_a-28+8i_b&=0\\<br /> 12i_a+6i_c+15i_d&=0\\<br /> 4i_e+10i_f+15i_d&=0\\<br /> 2i_g+13i_h+10i_f&=0\\<br /> 4i_e+2i_g+13i_h+15i_d&=0<br /> \end{align}[/itex]

Getting me something like:
[itex]-\frac{7}{39},\frac{49}{13},\frac{154}{39},\dots[/itex]

which I know is completely off.
 
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[itex]V_a[/itex] is the one w/ the 12 ohms.

[itex]V_h[/itex] is the 13 ohms one.
 
I'd probably just simplify it. If you keep your working for each step it will help when it comes to working out the voltages using the potential divider rule.