Prime Factorization

Objective:

Find the prime factorization of a composite number.

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 …

Determine whether the number is prime or composite.

1. 17

2. 12

3. 15

4. 24

5. 23

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

Method 2

60 2

30 2

15 3

5 5

1

Examples: Find the prime factorization.

1. 18

2. 28

3. 126

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