Electrical Engineering - Solving System of Equations on Polar Form

[joaolimatj]

Hi friends, I'm studying electrical engineering, and I'm having a super hard time figuring out how to solve systems of equations using polar coordinates.

Attached is one example of how to solve using systems and determinants, but in both ways, it does not work on polar coordinates... Is there any other way to do that?

The basic idea is to identify the loops and then create each equation and the calculator will solve to find each current for me...

Thanks a lot, friends!