Hi all. Not sure whether this is correct or not and I would like some guidance! Thanks...

Given that z1 = 4-j5 and z2 = -3+j4, Find the compelx number z1/z1-z2 in its simplest form.

This is what I have...

z1 / (z1 -z2) = (4 - j5) / (4 - j5 +3 -j4) = (4-j5)/(7 - j9)

=[ (4-j5) x (7+j9) ] / [ (7-j9) x (7+j9) ]

=[ (4x7 - (-5) 9) + j(4x9+(-5)x7) ] / (49+81)

=(73+j)/130

=73/130+j/130