1. Prime Factorization Objective: Find the prime factorization of a composite number.

2. A Prime Number: is a whole number greater than 1 that has exactly 2 factors, 1 and itself. Examples: 2 = 1 × 2 3 = 1 × 3 5 = 1 × 5 and 7, 11, 13 …  A Composite Number is a whole number greater than 1 that has more than two factors.  Examples: 4 = 1,2,4 6= 1,2,3,6 and 8, 9, 10 …

3. Examples: Determine whether the number is prime or composite. 1.17 _______________ 2.12 _______________ 3.15 _______________ 4.24 _______________ 5.23 _______________

4. Prime Factorization: Every composite number can be written as a product of prime numbers. This product is the prime factorization. You can use a factor tree to find the prime factorization.  Examples: Method 1 60 2 30 2 15 3 5 2 x 2 x 3 x 5 or 2 2 x 3 x 5  Method 2 100 50 2 25 2 5 5 1 5 2 x 2 x 5 x 5 or 2 2 x 5 2

5. Examples: Find the prime factorization.  1. 18  2. 28  3. 126

6. Homework:  Determine whether each number is prime or composite. 1.22 2.44 3.13 4.39 5.81 6.31  Find the prime factorization of each number. 7. 96 8. 42 9. 99 10. 64