How did they rewrite this?

1. Oct 13, 2009

Shackleford

How did they rewrite this?

A = 1 / (-2 + 4i)

A = -(1/10) - (1/5)i

2. Oct 13, 2009

Ed Aboud

Multiply the numerator and denominator of A by the complex conjugate of -2 + 4i

3. Oct 13, 2009

Shackleford

That's what I was thinking but wasn't sure. I haven't had to do that in a long time. lol.