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## Homework Statement

The circuit in the figure is composed of two batters (E1 = 5 V and E2 = 9 V) and four resistors (R1 = 110 W, R2 = 40 W, R3 = 50 W, and R4 = 50 W) as shown.

Find I1 and I3

## Homework Equations

Well we need to apply KCL. I know the respective voltages (Ohm's law) need to add up to 0.

## The Attempt at a Solution

I have tried like a million different equations for the 2 circuits present. I dont really understand circuits too well (which explains as to why I am posting/getting the wrong answer).

For the left loop:

I1R1 - I2R2 + E2 + I3R4 - E1 = 0 (Is it right to assume that I4 has equal current to I3?)

For the left loop:

I2R2 + I3R3 - E2 = 0

I1 + I2 = I3

To see the work that I did on the image to get the directions of the currents go to: http://i30.photobucket.com/albums/c309/hydr/showmepl-1.gif

I know the above equations are wrong, but I dont know whats wrong with them. They look right to me.

I solved for I1 first, but got the wrong answer. I know that if i add the left and right loop together then I should get the equation for the whole loop minus I2R2 and E2. I dont understand what Im doing wrong. I have inputed the respective values into a 3 x 3 matrix and solved for I1-3 with matlab, so there is no error in substitution.