Question

Which complex number is equivalent to (5 + 12i) − (9i2 − 6i), where i = −1 ?

Answer 1

Answer:

14 + 18i

Step-by-step explanation:

$(5 + 12i) - (9 {i}^{2} - 6i) \\ = (5 + 12i) - (9 \times (- 1) - 6i) \\ = (5 + 12i) - ( - 9 - 6i) \\ = (5 + 12i) + ( 9 + 6i) \\ = 5 + 12i + 9 + 6i \\ \red { \bold{ = 14 + 18i}}$