If a + bi is a root of a function, then a - bi is also a root of the
function.
When we have 9i, that makes a = 0 and b = 9
If 9i is a root
of f(x) then 0 - 9i, or -9i is also a root of f(x) -9i is correct!
Hope this helps! If you have any other questions or would like further explanation just let me know! :)
