Respuesta :

6 + 42i

Expanding the expression, by using FOIL acronym

(-4+2i)(3-9i)​

-12+36i+6i-18i²

-12 +42i -18i² Remember i²= -1

-12 + 42i -18(-1)

-12 + 42i +18

6 + 42i

2) Now we have that complex number in the form a +bi

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