How do you simplify (3+ 3i ) - ( 6- 9i )?

1 Answer
Dec 1, 2016

12i - 3

Explanation:

First, expand the terms in parenthesis. Take care when expanding a term with a negative sign to ensure your signs are correct - "-" x "-" is a "+":

3 + 3i - 6 + 9i

Next rearrange to get like terms together:

3i + 9i + 3 - 6

Now combine like terms to simplify:

(3 + 9)i + (3 - 6)

12i - 3