Electrical Engineering Op Amps Problem

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Bahester
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Homework Statement


http://i8.photobucket.com/albums/a45/bahester9/opamps1.jpg


Homework Equations


I know I can use KCL to solve at a node if I was looking for like a voltage. But I'm not sure really about the current, Ix.


The Attempt at a Solution

I know that Ix has to somehow be involved, so I tried to maybe do KCL at the node where Ix is. I know that there should be no current in or out of the op amp, so when I did my KCL equation for that node I got iR3 + iR4 = 0. However, there is no Ix in that equation either so I was confused as to if the equation should instead be iR3 + iR4 + Ix = 0. Then maybe solve for Ix? However I'm getting very confused and I think there's a simple way to do this, but I've confused myself a great deal.
 
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Bahester said:

Homework Statement


http://i8.photobucket.com/albums/a45/bahester9/opamps1.jpg


Homework Equations


I know I can use KCL to solve at a node if I was looking for like a voltage. But I'm not sure really about the current, Ix.


The Attempt at a Solution

I know that Ix has to somehow be involved, so I tried to maybe do KCL at the node where Ix is. I know that there should be no current in or out of the op amp, so when I did my KCL equation for that node I got iR3 + iR4 = 0. However, there is no Ix in that equation either so I was confused as to if the equation should instead be iR3 + iR4 + Ix = 0. Then maybe solve for Ix? However I'm getting very confused and I think there's a simple way to do this, but I've confused myself a great deal.

(Boy, that circuit sure is drawn goofy!)

Welcome to the PF.

Go ahead and solve for the voltages, and then just use V=IR to solve for the current.