Question

Simplify (4 − 8i)(2 − 7i).

8 + 56i2

−48 − 44i

64 − 44i

8 − 44i + 56i2

Answer 1

8 - 44i + 56i²

Explanation:

Use FOIL: (a + b)(c + d) = ac + ad + bc + bd

(4 - 8i)(2 - 7i)

= (4)(2) + (4)(-7i) + (-8i)(2) + (-8i)(-7i)

= 8 - 28i - 16i + 56i²

combine like terms

= 8 + (-28i - 16i) + 56i²

= 8 - 44i + 56i²