college algebra
posted by david on .
use the given zero to find the remaining zeros of each function.g(x)=x^3+3x^2+25x+75;zero:5i

If 5i is a zero, then so is +5i
So, we know that g(x) = (x^2+25)(x+a)
= x^3 + 25x + ax^2 + 25a
Looks like a=3
So, the remaining zero is x=3