
Combining like terms?
This is for a physics question, but I figured since it was mathbased, I might be able to post it here. The problem that I'm having is combining like terms  I know it's simple but for some reason I've forgotten.
Here's my problem:
I solved it up until here. Now I'm stuck.
C = (3.69i + 10.14j)  (8.312i + (4.8)j)
If only the 'i' terms can be combined with 'i' terms, and the 'j' terms only with 'j' terms, how would I do this?
Would it be 3.69i (8.312i) which would give me a positive answer or just 3.69i(8.312i) where I ignore the '' in between the two brackets (and subtract later) which would give me a negative answer?
Thanks for any help!

C = (3.69i + 10.14j)  (8.312i + (4.8)j)
=3.69i + 10.14j + 8.312i + 4.8j
=12.002i + 14.94j

Alright, thanks. I was afraid of that, because I've been doing those ones wrong then...
So, for instance, if I had say:
(4.1i + (3.75)j)  (1.30i + 2.25j)
I would get:
4.1i  3.75j  1.30i  2.25j which would equal 2.8i  6.0j?
If I wanted to square root that would it be, then, squ.rt. of (2.8)^2 + (6.0)^2? or would it be (2.8)^2  (6.0)^2?
Thanks again!