Question 1099893
Another zero is  {{{4+3i}}}.  A quadratic factor for P is  {{{(x-4-3i)(x-4+3i)=((x-4)-3i)((x-4)+3i)}}}
{{{(x-4)^2+9}}}
{{{x^2-8x+16+9}}}
{{{highlight_green(x^2-8x+25)}}}.


The OTHER quadratic factor of P?
You can use polynomial division if P is factorable.

.

.

.