Need help with Algebra 2. Please answer.

Write the expression as a complex number in standard form.

1. (5 + 2i) + (6 - 5i)

2. -3i (7 + i)

3. 1 + 2i / 3 - 8i

4. (3 - 2i) + 2i / (-1 + 7i) - (2 + 3i)

1. (5 + 2i) + (6 - 5i)=
5+2i+6-5i = 11 - 3i

2. -3i (7 + i)
-21i - 3i^2 ... Or i^2 = -1
then 3 - 21i

3. 1 + 2i / 3 - 8i
=
(1+2i)(3+8i)/(3-8i)(3+8i) =
(3+6i+8i+16i^2)/(9+64) =
(3-2i)/73

4. (3 - 2i) + 2i / (-1 + 7i) - (2 + 3i) =
(3 -2i +2i )/ (-1 + 7i -2 - 3i ) =
3/-3 +4i =
3(4i+3)/(4i+3)(4i-3) =
(9+12i) / -25

I hope i helped :D