Multiply. Write your answer in a +bi form.
-$(4+2 \mathrm{i})(5-7 \mathrm{i})$
A) $-14 i^{2}-18 i+20$
B) $34+18 \mathrm{i}$
C) $6+38 i$
D) $34-18 \mathrm{i}$

Question

Quizplus · Accepted Answer

To multiply the complex numbers, use the distributive property: $(4+2i)(5-7i) = 4(5) + 4(-7i) + 2i(5) + 2i(-7i)$. This simplifies to $20 - 28i + 10i - 14i^2$. Since $i^2 = -1$, $-14i^2 = 14$. Combine like terms to get $34 - 18i$.

Multiply Write Your Answer in a +Bi Form (4+2i)(5−7i)(4+2 \mathrm{i})(5-7 \mathrm{i})(4+2i)(5−7i)

Multiply Write Your Answer in a +Bi Form $(4+2 \mathrm{i})(5-7 \mathrm{i})$