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Multiply (9 − 4i)(2 + 5i).

2 Answers

3 votes

Answer:

38+37i

Explanation:

(9 − 4i)(2 + 5i)= 18+45i-8i-20i²= 18+20+37i= 38+37i

User Puudeli
by
4.9k points
2 votes

Answer:

38 + 37i

Explanation:

(9 − 4i)(2 + 5i)

FOIL

first: 9*2 = 18

Outer: 9*5i = 45i

inner: -4i * 2 = -8i

last : -4i * 5i = -20i^2 = -20(-1) = 20

Combine together

18+45i-8i +20

38 + 37i

User Sdicola
by
4.8k points