## Introductory Algebra for College Students (7th Edition)

composite; $3^{2} \cdot 7$
RECALL: A prime number is a number whose only factors are 1 and itself. A composite number is a number with factors other than one and itself. Note that: $9(7) = 63$ This means that $63$ has 7 and 9 as its factors. Thus, $63$ is a composite number. Factor $63$ completely to have: $63 \\=3(21) \\=3(3)(7)$ $\\=(3^{2})(7)$ The prime factorization of $63$ is: $=3^{2} \cdot 7$