In the next two tutorials we will add on other types of factoring. Note that if we multiply our answer out that we do get the original polynomial. Factors are the building blocks of multiplication. This method of factoring only works in some cases. To find the GCF of greater numbers, you can factor each number to find their prime factors, identify the prime factors they have in common, and then multiply those together.

Find the greatest common factor of and But the factored form of a four-term polynomial is the product of two binomials. When factoring 5 b out of 10 ab and 5 b , the remaining 2 a and 1 must still be added and multiplied by the common factor 5 b: The two groups 7 x x — 3 and 5 x — 1 do not have any common factors, so this polynomial cannot be factored any further. Intermediate Algebra Tutorial Group terms into pairs.

# Factoring Polynomials Using the GCF

Not too hard, is it? As shown above when we divide 2 x by 2 x we get 1, so we need a 1 as the third term inside of the. Rewrite the polynomial using the factored terms in place of the original terms.

Note that if we multiply our answer out, we do get the original polynomial. Factor out the like factor, 5, from the second group.

So our numerical GCF is 3. Find the greatest common factor of and When factoring 5 b out of 10 ab and 5 bthe remaining 2 a and 1 must still be added and multiplied by the common factor 5 b: A prime factor is similar to a prime number —it has only itself and 1 as factors.

When we divide it out of the second term, we are left with Example Problem Find the greatest common factor of 25 b 3 and 10 b 2.

The GCF of two numbers is the greatest number that is a factor of both of the numbers. Factor out the common binomial.

## Try Factor a Polynomial by Finding Its Greatest Common Factor

The method that you choose, depends on the make-up of the polynomial that you are factoring. To be in factored form, it must be written as a product of factors. Something to look forward to! That is ok, we treat it in the same manner that we do when we have a monomial GCF.

The correct answer ledson a 5 8 a — Find the GCF of the first pair of terms.

# Greatest Common Factor

Factor the common factor 5 out of the second group. Before we get started, it may be helpful for you to review the Dividing Monomials lesson. How to Succeed in a Math Class for some more suggestions. The process of breaking a number down into its prime factors is called prime factorization.

Notice that you arrive at the same simplified form whether you factor out the GCF immediately or if you pull out factors individually. When you factor a polynomial, you are trying to find the quantities that you multiply together in order to create the polynomial. Note that if all terms have the same variable, the GCF for the variable part is that variable raised ny the lowest exponent that is listed.

If we use the exponent 8, we are in trouble.

Sum of the products: Example Problem Find the greatest common factor of 81 c 3 d and 45 c 2 d 2. Think of numbers that are factors of both 56 and C a 5 a — 1 Incorrect. Finally, pull any common binomials out of the factored groups.

## Factoring by grouping

lfsson Likewise to factor a polynomialyou rewrite it as a product. Product of a number and a sum: You can then use the distributive property to rewrite the polynomial in a factored form.

There are several methods that can be used when factoring polynomials. These are practice problems to help bring you to the next level.