algebra help needed

Question

Multiply and simplify: (7 – 2i)(8 −3i)
Write the answer in the form a + bi, where a and b are real numbers.

Answer 1

Well, since i = √-1, then i² = -1.

 

(7 - 2i)(8 - 3i) = 56 - 21i - 16i - 6

 

Why - 6? Because a negative times a negative gives a positive, but i² = -1, so it turns it negative.

 

50 - 37i