View attachment 365618
Set my mesh currents for I2 and I3 to be counterclockwise, not convention necessarily but should still be fine as far as I’ve learned. Got I1 = 3A, I2 = 4A, I3 = 9A, but the answers on my homework key are I1 = 4.984A, I3 = -7.1A, and V1 = -32.84V. Why the discrepancy and/or where did I go wrong in my method?

 

you messed up sign of the last term in your first equation. it is not +2*I3, it is -2*I3.

 

you messed up sign of the last term in your first equation. it is not +2*I3, it is -2*I3.

Thanks! Got it a little bit later, being more careful now.

 

your work does not show where V1 is but it has to be voltage across first current source. also you made typo for text book answer for I1.