# 3.09 Polynomial identities and complex numbers

## Interactive practice questions

Complete the factoring by filling in the empty box.

$9ix-54=9i\left(\editable{}\right)$9ix54=9i()

Easy
Approx a minute

Factor the expression $x^2+25$x2+25. Leave your answer in terms of $i$i.

Factor the expression $64x^2+81$64x2+81. Leave your answer in terms of $i$i.

Factor the expression $3x^2+108$3x2+108. Leave your answer in terms of $i$i.

### Outcomes

#### MGSE9-12.N.CN.8

Extend polynomial identities to include factoring with complex numbers. For example, rewrite x^2 + 4 as (x + 2)(x - 2i)