Multiply the complex numbers:
(8 – 4i) · (6 + i)
= (8 – 4i) · 6 + (8 – 4i) · i
= 8 · 6 – 4i · 6 + 8 · i – 4i · i
= 48 – 24i + 8i – 4i² (but, i² = – 1)
= 48 – 24i + 8i – 4 · (– 1)
= 48 – 24i + 8i + 4
= 48 + 4 – 24i + 8i
= 52 – 16i <———— this is the answer.
I hope this helps. =)
