1) 4b-5t(-a-3)i=7-8i

2) (7+4i) - (l+2i)

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

8 answers

1. I don't know

2. is -14 + 8i

3. is 2i+7-l

I hope this helps! :)
thank you
but can u show me how u got it?
Oops, I am Anonymous! Sorry!

Anyways for 1, I still don't know.

For 2, it is -14 + 8i.

For 3, it is 2i+7-l

I hope this helps! :)
i know i mean how did you get it like how your answer so i can use it for my other questions.
1. 4b-5t(-a-3)i=7-8i
You don't say what you want.
I see 3 variables in one equation, are you solving for one of them or what?

2. (7+4i) - (l+2i)
is that supposed to say (7+4i) - (1+2i) ?
then
= 7+4i - 1 - 2i
= 6 + 2i

3.
(3+2i) (-2+4i)
= -6 + 12i - 4i + 8i^2
= -6 + 8i - 8 , remember i^2 -1
= -14 + 8i
Sorry, I didn't see your post before my second post. I made a typo error as well in my two posts. I meant to say:

2. is 2i+7-l

3. is -14 + 8i

For 2:

I got my answer off researching.

(7+4i) - (l+2i)

Multiply i and 4 = 4i
Multiply i and 1 = i

7+4*i = 7+4i

Multiply i and 2 = 2i
Multiply i and 1 = i

l+2*i = l+2i

Subtract polynomials 7+4i & l+2i. Subtract terms in one polynomial with any like terms in the other polynomial.

Be careful with "-" in front of l+2i. Used on all terms in it.

4i - 2i = 2i

The answer is 2i+7-l

(7+4*i)-(l+2*i) = 2i+7-l

The final answer is:

2i+7-l

For 3:

I can't really explain, even though I will try.

(3+2i) (-2+4i) =

(3 + (2 * i)) * ((-2) + (4 * i)) =

-14 + 8 i

That's as best as I could explain both. I got both from researching and doing the problems, so I can't really explain by that.

I hope this helps?
Reiny is correct for 2, I forgot to subtract 1 from 7 to get her answer. Sorry!!

P.S. Go with Reiny, she is a tutor on this website, I was just trying to help though.
I am Anonymous again! I don't know why it keeps doing this!

"Reiny is correct for 2, I forgot to subtract 1 from 7 to get her answer. Sorry!!

P.S. Go with Reiny, she is a tutor on this website, I was just trying to help though."