Answer:
24 + 10i
Step-by-step explanation:
(15 + 6i) - (-9 - 4i) = 15 + 6i + 9 + 4i = 24 + 10i
(15 + 6i) - (- 9 - 4i)
15 + 6i + 9 + 4i
15 + 9 + 6i + 4i
therefore, (15 + 6i) - ( -9 - 4i) = 24 + 10i
