I originally thought you would find total impedance by doing the rectangular to polar conversion equation. But then I was taking a test for a job, and when I did the the the rectangular to polar equation the answer didn't match.Well, I'm pretty sure the first part is just the conversion from regular resistance, capacitance, and inductance to the real +/- imaginary impedance. This link will help you understand it more:
http://www.allaboutcircuits.com/vol_2/chpt_5/2.html
You'd want to use those equations when you're finding the Total Impedance in a circuit.
The second equation I'm not entirely sure about. Where did you get the pictures from?
by Aaron Carman
by Jake Hertz
by Aaron Carman