Question

How do you multiply `(5+5i)(-3-7i)`?

Answer 1

There are at least two ways to do the multiplication. I recommend, F.O.I.L.: `-15 - 35i - 15i - 35i^2 = 20 - 50i`

Explanation:

`i^2 = -1` this turns `- 35i^2` into `+ 35`