Factoring Polynomials Using the Greatest Common Factor (GCF)

Definition of Factors

Factoring a polynomial involves finding the quantities that, when multiplied together, produce the original polynomial. Factors are numbers or expressions that divide evenly into a given number or expression.

Key Facts

  1. Definition of Factors:
    • When factoring a polynomial, you are trying to find the quantities that you multiply together to create the polynomial.
    • Factors are the numbers or expressions that divide evenly into a given number or expression.
  2. Greatest Common Factor (GCF):
    • The GCF for a polynomial is the largest monomial that is a factor of each term in the polynomial.
    • The GCF must be a factor of every term in the polynomial.
    • Finding the GCF involves identifying the highest power of each variable that appears in all the terms.
  3. Process of Factoring Using GCF:
    • Find the GCF of all the terms in the polynomial.
    • Express each term as a product of the GCF and another factor.
    • Use the distributive property to factor out the GCF.
  4. Examples:
    • Example 1: Factoring Using the GCF
      • Polynomial: 6x^2 + 9x
      • GCF: 3x
      • Factored form: 3x(2x + 3)
    • Example 2: Factoring Polynomials
      • Polynomial: 12x^3y^2 + 8xy^3
      • GCF: 4xy^2
      • Factored form: 4xy^2(3x^2 + 2y)
    • Example 3: Factoring Polynomials
      • Polynomial: 15a^2b – 10ab^2
      • GCF: 5ab
      • Factored form: 5ab(3a – 2b)

Greatest Common Factor (GCF)

The GCF of a polynomial is the largest monomial that is a factor of every term in the polynomial. The GCF must be a factor of every term in the polynomial. To find the GCF, identify the highest power of each variable that appears in all the terms.

Process of Factoring Using GCF

  1. Determine the GCF of all the terms in the polynomial.
  2. Express each term as a product of the GCF and another factor.
  3. Use the distributive property to factor out the GCF.

Examples

Example 1: Factoring Using the GCF

  • Polynomial: 6x^2 + 9x
  • GCF: 3x
  • Factored form: 3x(2x + 3)

Example 2: Factoring Polynomials

  • Polynomial: 12x^3y^2 + 8xy^3
  • GCF: 4xy^2
  • Factored form: 4xy^2(3x^2 + 2y)

Example 3: Factoring Polynomials

  • Polynomial: 15a^2b – 10ab^2
  • GCF: 5ab
  • Factored form: 5ab(3a – 2b)

Sources

FAQs

 

What is factoring by GCF?

Factoring by GCF involves finding the greatest common factor (GCF) of all the terms in a polynomial and then expressing each term as a product of the GCF and another factor. The GCF is then factored out using the distributive property.

 

How do I find the GCF of a polynomial?

To find the GCF of a polynomial, identify the highest power of each variable that appears in all the terms. The GCF is the product of these highest powers.

 

When can I use factoring by GCF?

Factoring by GCF can be used when every term in the polynomial has a common factor.

 

What are the steps for factoring by GCF?

  1. Find the GCF of all the terms in the polynomial.
  2. Express each term as a product of the GCF and another factor.
  3. Use the distributive property to factor out the GCF.

 

Can I factor any polynomial using GCF?

No, factoring by GCF is only possible when every term in the polynomial has a common factor.

 

What are some examples of factoring by GCF?

  • 6x^2 + 9x = 3x(2x + 3)
  • 12x^3y^2 + 8xy^3 = 4xy^2(3x^2 + 2y)
  • 15a^2b – 10ab^2 = 5ab(3a – 2b)

 

What are the benefits of factoring by GCF?

Factoring by GCF can simplify polynomials, make them easier to solve, and reveal important properties of the polynomial.

 

What are some common mistakes to avoid when factoring by GCF?

  • Not finding the GCF correctly
  • Not expressing each term as a product of the GCF and another factor
  • Not using the distributive property correctly