Greatest Common Factor

AIM: How can we factor using the Greatest Common Factor?

Use this method if numbers are large. Use a factor tree. List all the prime factors (even if the numbers repeat). Multiply the common prime factors to figure out the GCF.

2. Prime Factorization

List the factors of each number.

Circle the largest common factor.

​1. List Factors

Two Methods

Multiple Choice

What are all the factors of 10?

• 1, 2, 5, 10

• 1, 2, 3, 4, 5, 10

• 1, 10

• 1, 2, 4, 8

Multiple Choice

What is the GCF of this polynomial: $$10x^3+15x^{5\ }$$  

• $$5x^2$$  

• $$5x^3$$  

• $$10x$$  

• $$10x^3$$  

Open Ended

Ryan is trying to factor this polynomial:

$$12x^2-20x^4$$  

He says that the GCF is  $$2x^2$$  Do you agree with Ryan? Explain why.

Multiple Select

After our notes and work today, I feel ....

• I still do NOT understand at all.

• I understand this a little bit.

• I think I got this down.

• This is so easy. Can we do this the rest of the semester?