Posted by Paige on Thursday, October 15, 2009 at 8:51pm.
The answer for (7+5i)+(4+2i) is 3+7i. But I got 386i. I combined 28 and 10i^2 to get 38, and I combined 20i and 14i to get 6il So all together this was 28+6i+10, which resulted in 386i. Could you please tell me where I went wrong?

Algebra II  MathMate, Thursday, October 15, 2009 at 8:58pm
(7+5i)+(4+2i)
The answer is for an addition.
You did a multiplication. Hope that explains it. 
Algebra II  Francene, Thursday, October 15, 2009 at 9:16pm
(7+5i) + (4+2i)=> 7+5i4+2i :.
74+5i+2i = 3 + 7i 
Algebra II  MathMate, Thursday, October 15, 2009 at 9:17pm
Exactly! :)