Answer
The prime factorization is $$2 \times 3 \times 3$$ or $$2 \times 3^2$$
Work Step by Step
Using the factor tree, you will find that $2$, $3$, and $3$ are the prime numbers that multiply to $18$.
$$2 \times 3 \times 3$$
OR
$$ 2 \times 3^2$$
