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April 18, 2014

April 18, 2014

Posted by **Sara** on Thursday, August 16, 2012 at 10:48am.

1. 5+(2+3i) + (-3-7i)

= 4 + -4i

2. (5-10i) - (2+i)

= 7 - 9i

3. -5i(2-3i)

= -10i - 15

4. (2+3i)(-3-7i)

= (1)(4i)

- Algebra2 -
**Sara**, Thursday, August 16, 2012 at 10:53amI Made a Mistake Problem #4 Answer Is

21-20i

- Algebra2 -
**Steve**, Thursday, August 16, 2012 at 11:33amNope. I'd be interested in how you got your answers.

1. 5+(2+3i) + (-3-7i) = (5+2-3) + (3-7)i = 6 - 4i

2. (5-10i) - (2+i) = (5-2) + (-10-1)i = 3 - 11i

3. correct, but in standard form is -15 - 10i

4. (2+3i)(-3-7i) = -6 - 14i - 9i - 21i^2 = -6 - 23i + 21 = 15 - 23i

- Algebra2 -
**Sara**, Thursday, August 16, 2012 at 11:38amI went back and I corrected problem 2 and 3.

In problem 2 I found my mistake, But in problems 1 and 4 I'm stuck and can't figure out how you got those answers.

I did the problems at least 4 times already and I keep getting the same answers:/

- Algebra2 -
**Sara**, Thursday, August 16, 2012 at 11:41amI think i know what i did wrong in problem 4!

My multiplication is wrong!

- Algebra2 - My Bad! -
**Steve**, Thursday, August 16, 2012 at 11:49amOuch! I blew it in #1. You are correct. Dunno how I got 6.

- Algebra2 -
**Sara**, Thursday, August 16, 2012 at 11:52amLol:D

You were being speeding threw the problems just like me!

i did that in problem 4!

I got the right answer now!

Thank you!

- Algebra2 -
**Sara**, Thursday, August 16, 2012 at 11:54amSorry "being" shouldn't have been there.

Another mistake!

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