## Algebra: A Combined Approach (4th Edition)

$2 \times 2 \times 2 \times 2 \times 2 \times 5 \times 5$
800 is the product of 10 and 80 10 is the product of 2 and 5, and 80 is the product of 10 and 8, so we can write, $800 = 10 \times 80 = 2 \times 5 \times 80 = 2 \times 5 \times 8 \times 10$ Now 2 and 5 are prime, yet 10 and 8 are not, however $10 = 2 \times 5$ and $8 = 2 \times 2 \times 2$ so, $800 = 2 \times 5 \times 8 \times 10 = 2 \times 5 \times 2 \times 2 \times 2 \times 5 \times 2$ therefore the prime factorization of 800 = $2 \times 2 \times 2 \times 2 \times 2 \times 5 \times 5$