please help me out and explain it to me

Answer:
Answer is option d 14+18i
Step-by-step explanation:
[tex]given \: expression \: is \\ (5 + 12i) - (9 {i}^{2} - 6i) \: \: \: where \: i = \sqrt{ - 1} \: \: \\ = 5 + 12i - 9 {i }^{2} + 6i \\ = 18i + 5 - 9( - 1) \\ 18i + 5 + 9 \\ = 18i + 14[/tex]
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