x + yi + 2x + 2yi + 3i = 9 this first step is just distributing the 2
3x + 3yi = -3i + 9 this step is adding like terms
x+ yi = 3 - i this step is dividing by 3 to all terms... Lowest common factor
then subtracting 3i to the right side of the equation
so x =3 and y= -1
if that the full question?