(6 + 3i) + (8 + 4i) (since you're adding, there's no need to change signs, just add like terms) 6 + 8 = 14 3i + 4i = 7i 7i + 14
(7i + 14) - (1 + 4i) (since you're subtracting, you have to change signs for the second binomial and then add like terms) 7i + 14 - 1 - 4i 7i - 4i = 3i 14 - 1 = 13 3i + 13