Study Guide
Factors and Greatest Common Factor

 

If two or more numbers are multiplied, each number is a factor of the product.

 

Definition

Example

Prime Number

A prime number is a whole number, greater than 1, whose only factors are 1 and itself

5

Composite Number

A composite number is a whole number, greater than 1, that is not prime.

10

Prime Factorization

Prime factorization occurs when a whole number is expressed as a product of factors that are all prime numbers.

45 = 32 · 5

Greatest Common Factor (GCF)

The greatest common factor of two or more integers is the greatest number than is a factor of the integers.

The GCF of 12 and 30 is 6

The GCF of two or more monomials is the product of their common factors, when each monomial is expressed in factored form.

Directions: State whether each number is prime or composite. If the number is composite, find its prime factorization.

28

composite
22 · 7

61

prime

112

composite
24 · 7

2865

composite
3 · 5 · 191

Directions: Factor each expression completely. Do NOT use exponents.

−34

−1 · 2 · 17

−150

−1 · 2 · 3 · 5 · 5

56pq3

2 · 2 · 2 · 7 · p · q · q · q

−108(cd)2

−1 · 2 · 2 · 3 · 3 · 3 · c · c · d · d

Directions: Find the GCF of the given monomials.

−45, 15

15

169, 13

13

−20, 440

20

49x, 343x2

49x

4a7b, 28ab

4ab

97y, 12x, −8y

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