(I'll assume that the blank spaces are PLUS signs ( + ),
as they usually are on Brainly.)
The mystery complex number is (5 - i) .
(3 + 2i) x (5 - i) = (17 + 7i)
FOIL it out and you'll see it.
Answer:

Step-by-step explanation:
refer to solution in the picture
Hey there!

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