Answer:
The missing term is [tex]-2-24i[/tex]
Step-by-step explanation:
Let us assume missing term be [tex]x[/tex].
[tex]x + (7-3i)+(5+9i)+13i=10-5i[/tex]
Subtract [tex]7-3i[/tex], [tex]5+9i[/tex] and [tex]13i[/tex] from both sides.
[tex]x + (7-3i)+(5+9i)+13i-(7-3i)-(5+9i)-13i=10-5i-(7-3i)-(5+9i)-13i\\x=10-5i-(7-3i)-(5+9i)-13i\\\\x=-2-24i[/tex]
