Question 1091156
This is a problem involving arithmetic using complex numbers.
It is no different from working with polynomials, except that
you can use {{{i^2=-1}}} to simplify.
{{{(4 + 9i)(-7-i)-(6-2i)=-28-4i-63i-9i^2-(6-2i)=-28-67i-9(-1)-(6-2i)=-28-67i+9-(6-2i)=-19-67i-(6-2i)=-19-67i-6+2i=-25-65i}}}