Engineering Help finding error in my Circuit Analysis

[mkematt96]

Homework Statement

Homework Equations

The Attempt at a Solution

My values for i1,i2,and i3 were: -.005179,-.002857 and .004857. When I ran the same circuit through LT Spice the values they gave me were .00059081,.000809628, and .00119037. Where did I make my error?
* as a side not I notices I only have 1000 instead of 10,000 in my matrix for the first line. The values I got were using 10,000 instead of 1000 in the first line.

 

[cnh1995]

Since you know the answer from your simulation result, I'd post the values I am getting.
I am getting V_AB= 7.221V and I_R3= 1.4mA.

For I₁, I₂ and I₃ (labelled differently in my working) I am getting the same values as your LTspice result (just 10 times more, since you used 10000 instead of 1000).

 

[The Electrician]

I see a couple of mistakes. In your equation for loop 1 you left out the 5k resistor.

In your equation for the super mesh, you have a term 4k(I1 - I2). This should be 4k(I2 - I1).

 

[mkematt96]

I see a couple of mistakes. In your equation for loop 1 you left out the 5k resistor.

In your equation for the super mesh, you have a term 4k(I1 - I2). This should be 4k(I2 - I1).

After making these changes I got my numbers to match the LT Spice number! Thanks!