1. The problem statement, all variables and given/known data Given the equivalent impedance of a circuit can be calculated by the expression Z= (Z_1 Z_2)/(Z_1+ Z_2 ) If Z1 = 4 + j10 and Z2 = 12 – j3, calculate the impedance Z in both rectangular and polar forms. 2. Relevant equations j2=-1 3. The attempt at a solution Z= ((4+j10)×(12-j3))/((4+j10)+(12-j3)) Z=(48+j12-j120-j^2 30 )/(16-j7) Z= (48+j12-j120-(-1)30)/(16-j7) Z= (48-j108+30)/(16-j7) Z= (78-j108)/(16-j7) I've got completely stuck i'm afraid. From searching about, it appears it would be easier to convert this straight into polar form. My notes are quite shocking on this, please see attached. I'm using microsoft mathematic software as my calculator, but having absolutely no joy figuring out how to do this. If anybody can offer some assistance, even in just how to get the answer in the attached i'm sure i can work the rest out. Thanks.