Answer
$\quad a-bi,\quad 3-i$
Work Step by Step
Conjugate Zeros Theorem (p. 291)
If the polynomial $P$ has real coefficients and
if $a+bi$ is a zero of $P$, then its complex conjugate $a-bi$ is also a zero of $P$.
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Blanks: $\quad a-bi,\quad 3-i$