Answer:
The missing term is (2 + i) [5 - (1 + 2i)]
Step-by-step explanation:
Let the missing term be X
(1 + 2i)(2 + i) + X = 5(2 + i)
X = 5(2 + i) - (1 + 2i)(2 + i)
X = (2 + i) [5 - (1 + 2i)]
