Maximizing Power Transfer in Circuits: Seeking Help with Homework Statement

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DollarBill
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Homework Statement


I'm looking for the maximum power transferred to resistor R. I know how to approach the problem, but not getting the right answer and was wondering if someone could just look over my work.
[PLAIN]http://img854.imageshack.us/img854/1412/screenshot20110604at115.png

Homework Equations


V=i*R
i1 -> Far Left Loop, Clockwise
i2 -> Middle Loop, Clockwise
i3 -> Far Right Loop (loop containing the current source and 30 kilo-Ohm Resistor), Clockwise
V1 -> Voltage through current source

The Attempt at a Solution



Only concerned about Vth for now:
[PLAIN]http://img580.imageshack.us/img580/7527/image001tr.jpg

(1) 100 + 10*i1 - 40(i1-i2) = 0
(2) 40(i1-i2) + 22*i2 + V1 = 0
(3) -30*i3 - V1 = 0
(4) i3 - i2 = 0.003v0 = 0.003(40)(i1-i2)

Simplified:
(1) -30i1 + 40i2 = -100
(2) 40i1 - 18i2 + V1 = 0
(3) 30i3 + V1 = 0
(4) 0.12i2 + 0.88i2 - i3 = 0


Vth = V1 = 903.87 V (Which I know isn't right)
 
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Could you be a little more specific? I've checked my signs a few times, but am still having trouble seeing where I messed up.
 
You have 100 V potential at the upper left corner of the first loop. Then you follow the current through the 10 kohm resistor. The current flows from the higher potential to the lower one, as the water flows from a hill to the valley. Is the potential higher of lower at the other end of it?

ehild