Google

To **factor the greatest common factor (GCF) from a polynomial**, apply the Distributive Property in reverse. Whereas multiplying a polynomial by a monomial uses $$a(b + c) = ab + ac$$ to expand, factoring reverses the process using $$ab + ac = a(b + c)$$ to condense. The procedure has four steps:

1. **Find the GCF of all the terms of the polynomial.** Use prime factorization to identify the largest expression that divides evenly into every term.
2. **Rewrite each term as a product using the GCF.** Express each term as the GCF multiplied by the remaining factor.
3. **Use the "reverse" Distributive Property to factor the expression.** Write the GCF outside a single set of parentheses containing the remaining factors.
4. **Check by multiplying the factors.** Distribute the GCF back through the parentheses to verify that the result matches the original polynomial.

For example, to factor $$2x + 14$$: the GCF of $$2x$$ and $$14$$ is $$2$$, so rewrite as $$2 \cdot x + 2 \cdot 7$$, then factor to get $$2(x + 7)$$. Checking: $$2(x + 7) = 2x + 14$$ ✓. This process is the reverse of multiplying a polynomial by a monomial — starting with the product and recovering the factors.

Factoring the Greatest Common Factor from a Polynomial

Factor $$12x - 60$$ by extracting the greatest common factor.

**Step 1 — Find the GCF of $$12x$$ and $$60$$:** Write out the prime factors of each term: $$12x = 2 \cdot 2 \cdot 3 \cdot x$$ and $$60 = 2 \cdot 2 \cdot 3 \cdot 5$$. The factors common to both are $$2, 2,$$ and $$3$$, so $$\text{GCF} = 2 \cdot 2 \cdot 3 = 12$$.

**Step 2 — Rewrite each term as a product of the GCF:** Express $$12x = 12 \cdot x$$ and $$60 = 12 \cdot 5$$, giving $$12 \cdot x - 12 \cdot 5$$.

**Step 3 — Factor out the GCF using the reverse Distributive Property:** $$12(x - 5)$$.

**Step 4 — Check by multiplying:** $$12(x - 5) = 12 \cdot x - 12 \cdot 5 = 12x - 60$$ ✓.

The factored form is $$12(x - 5)$$. This example demonstrates factoring when the GCF is a larger number ($$12$$) that requires prime factorization to identify, rather than being immediately obvious from inspection.

Factoring $$12x - 60$$

Factor $$4y^2 + 24y + 28$$ by extracting the greatest common factor from all three terms of the trinomial.

**Step 1 — Find the GCF of $$4y^2$$, $$24y$$, and $$28$$:** Factor each term into primes and expanded variables: $$4y^2 = 2 \cdot 2 \cdot y \cdot y$$, $$24y = 2 \cdot 2 \cdot 2 \cdot 3 \cdot y$$, and $$28 = 2 \cdot 2 \cdot 7$$. The factors shared by all three terms are two $$2$$s, so $$\text{GCF} = 2 \cdot 2 = 4$$.

**Step 2 — Rewrite each term as a product of the GCF:** Express $$4y^2 = 4 \cdot y^2$$, $$24y = 4 \cdot 6y$$, and $$28 = 4 \cdot 7$$, giving $$4 \cdot y^2 + 4 \cdot 6y + 4 \cdot 7$$.

**Step 3 — Factor out the GCF:** $$4(y^2 + 6y + 7)$$.

**Step 4 — Check by multiplying:** $$4(y^2 + 6y + 7) = 4 \cdot y^2 + 4 \cdot 6y + 4 \cdot 7 = 4y^2 + 24y + 28$$ ✓.

The factored form is $$4(y^2 + 6y + 7)$$. This example extends GCF factoring from binomials to trinomials. The same four-step process applies — the only difference is that the GCF must be a factor of all three terms, not just two, and each of the three terms is rewritten using the GCF before factoring.

Factoring $$4y^2 + 24y + 28$$

Factor $$5x^3 - 25x^2$$ by extracting the greatest common factor, which in this case includes a variable component.

**Step 1 — Find the GCF of $$5x^3$$ and $$25x^2$$:** Factor each term into primes and expanded variables: $$5x^3 = 5 \cdot x \cdot x \cdot x$$ and $$25x^2 = 5 \cdot 5 \cdot x \cdot x$$. The factors common to both are one $$5$$ and two $$x$$s, so $$\text{GCF} = 5 \cdot x \cdot x = 5x^2$$.

**Step 2 — Rewrite each term as a product of the GCF:** Express $$5x^3 = 5x^2 \cdot x$$ and $$25x^2 = 5x^2 \cdot 5$$, giving $$5x^2 \cdot x - 5x^2 \cdot 5$$.

**Step 3 — Factor out the GCF:** $$5x^2(x - 5)$$.

**Step 4 — Check by multiplying:** $$5x^2(x - 5) = 5x^2 \cdot x - 5x^2 \cdot 5 = 5x^3 - 25x^2$$ ✓.

The factored form is $$5x^2(x - 5)$$. This example shows that the GCF of a polynomial can be a monomial containing both a numerical factor and a variable factor. When finding the GCF of expressions with variables, include each shared variable raised to the lowest power present across all terms — here, $$x^2$$ (the lower of $$x^3$$ and $$x^2$$).

Factoring $$5x^3 - 25x^2$$

When factoring a polynomial whose **leading coefficient is negative**, the GCF is taken as negative. To apply this rule, first ignore the signs of all terms and determine the GCF of their absolute values (including any shared variable factors). Then attach a negative sign to that GCF. When the negative GCF is factored out using the reverse Distributive Property, the signs of all terms inside the parentheses are reversed compared to the original expression — negative terms become positive and positive terms become negative. The same four-step factoring procedure applies: find the (negative) GCF, rewrite each term as a product of the GCF, factor using the reverse Distributive Property, and check by multiplying. For example, to factor $$-8y - 24$$, the GCF of $$8y$$ and $$24$$ is $$8$$, but since the leading coefficient is negative, $$-8$$ is used as the GCF, yielding $$-8(y + 3)$$.

Factoring with a Negative Leading Coefficient

Factor $$-8y - 24$$ by extracting the greatest common factor, noting that the leading coefficient is negative.

**Step 1 — Find the GCF:** Ignoring the signs, find the GCF of $$8y$$ and $$24$$. Factor each into primes: $$8y = 2 \cdot 2 \cdot 2 \cdot y$$ and $$24 = 2 \cdot 2 \cdot 2 \cdot 3$$. The common factors are three $$2$$s, so the numerical GCF is $$2 \cdot 2 \cdot 2 = 8$$. Because the expression has a negative leading coefficient, use $$-8$$ as the GCF.

**Step 2 — Rewrite each term using the GCF:** Express $$-8y = (-8) \cdot y$$ and $$-24 = (-8) \cdot 3$$, giving $$(-8) \cdot y + (-8) \cdot 3$$.

**Step 3 — Factor out the GCF:** $$-8(y + 3)$$.

**Step 4 — Check by multiplying:** $$-8(y + 3) = -8 \cdot y + (-8) \cdot 3 = -8y - 24$$ ✓.

The factored form is $$-8(y + 3)$$. Factoring out the negative GCF reverses the signs inside the parentheses — both terms that were originally negative appear as positive inside $$(y + 3)$$.

Factoring $$-8y - 24$$

Factor $$-6a^2 + 36a$$ by extracting the greatest common factor, which includes both a negative coefficient and a variable.

**Step 1 — Find the GCF:** Ignoring the signs, determine the GCF of $$6a^2$$ and $$36a$$. Factor each: $$6a^2 = 2 \cdot 3 \cdot a \cdot a$$ and $$36a = 2 \cdot 2 \cdot 3 \cdot 3 \cdot a$$. The shared factors are one $$2$$, one $$3$$, and one $$a$$, so the GCF is $$6a$$. Because the leading coefficient is negative, use $$-6a$$ as the GCF.

**Step 2 — Rewrite each term using the GCF:** Express $$-6a^2 = (-6a) \cdot a$$ and $$36a = (-6a) \cdot (-6)$$, giving $$(-6a) \cdot a + (-6a)(-6)$$.

**Step 3 — Factor out the GCF:** $$-6a(a - 6)$$.

**Step 4 — Check by multiplying:** $$-6a(a - 6) = -6a \cdot a + (-6a)(-6) = -6a^2 + 36a$$ ✓.

The factored form is $$-6a(a - 6)$$. This example combines two features: the GCF includes a variable component ($$a$$, the lowest power of $$a$$ present in both terms) and is made negative because of the negative leading coefficient. The negative GCF causes the sign of the second term to flip — the original $$+36a$$ becomes $$-6$$ inside the parentheses.

Factoring $$-6a^2 + 36a$$

**Factoring by grouping** is a technique for factoring polynomials when no single factor is common to all terms. It is especially useful for four-term polynomials. The idea is to split the polynomial into smaller groups of terms, factor the GCF out of each group separately, and then extract the common binomial factor that emerges.

The procedure has four steps:

1. **Group terms with common factors.** Separate the polynomial into two pairs of terms, choosing pairs that share a common factor.
2. **Factor out the common factor in each group.** Apply GCF factoring within each pair independently.
3. **Factor the common factor from the expression.** After factoring each group, a common binomial factor should appear in both groups — factor it out using the reverse Distributive Property.
4. **Check by multiplying the factors.** Distribute to verify the product equals the original polynomial.

When the second group involves subtraction, take special care with signs while factoring out its GCF — factoring out a negative value reverses the signs inside the parentheses and is often necessary to produce a matching binomial in both groups.

Factoring by Grouping

Factor $$xy + 3y + 2x + 6$$ using the grouping method.

No single factor is common to all four terms, so apply factoring by grouping.

**Step 1 — Group terms with common factors:** Pair the first two terms and the last two terms: $$(xy + 3y) + (2x + 6)$$.

**Step 2 — Factor the GCF from each group:** The GCF of $$xy$$ and $$3y$$ is $$y$$: $$y(x + 3)$$. The GCF of $$2x$$ and $$6$$ is $$2$$: $$2(x + 3)$$. The expression becomes $$y(x + 3) + 2(x + 3)$$.

**Step 3 — Factor the common binomial:** Both terms share the factor $$(x + 3)$$. Factor it out: $$(x + 3)(y + 2)$$.

**Step 4 — Check by multiplying:** $$(x + 3)(y + 2) = xy + 2x + 3y + 6 = xy + 3y + 2x + 6$$ ✓.

The factored form is $$(x + 3)(y + 2)$$.

Factoring $$xy + 3y + 2x + 6$$

Factor $$x^2 + 3x - 2x - 6$$ using the grouping method.

No single factor is common to all four terms, so apply factoring by grouping.

**Step 1 — Group terms with common factors:** Pair the first two terms and the last two terms: $$(x^2 + 3x) + (-2x - 6)$$.

**Step 2 — Factor the GCF from each group:** The GCF of $$x^2$$ and $$3x$$ is $$x$$: $$x(x + 3)$$. For the second group, the GCF of $$-2x$$ and $$-6$$ is $$-2$$ (use the negative GCF so that the binomial inside matches the first group): $$-2(x + 3)$$. The expression becomes $$x(x + 3) - 2(x + 3)$$.

**Step 3 — Factor the common binomial:** Both terms share the factor $$(x + 3)$$. Factor it out: $$(x + 3)(x - 2)$$.

**Step 4 — Check by multiplying** to confirm the result equals the original expression.

The factored form is $$(x + 3)(x - 2)$$. When the second group begins with a negative term, be careful with signs when factoring its GCF — choosing the negative GCF (here $$-2$$ rather than $$2$$) reverses the signs inside the parentheses and produces the matching binomial factor needed for step 3.

Factoring $$x^2 + 3x - 2x - 6$$

An operations analyst is streamlining a production cost formula to identify shared expenses. To correctly factor the Greatest Common Factor (GCF) from the cost polynomial, in what order should the following steps be performed?

A logistics coordinator is simplifying a shipping cost formula by factoring out the greatest common factor (GCF). Arrange the standard steps for factoring the GCF from a polynomial in the correct order.

A budget analyst is simplifying a departmental expense formula, $15x + 15y$, to identify a shared hourly rate. By rewriting the expression as $15(x + y)$, the analyst is applying which mathematical property in reverse?

A business analyst is simplifying a revenue formula to identify shared cost drivers across different departments. Match each mathematical term or process with its correct role in the procedure of factoring out the Greatest Common Factor (GCF).

A payroll specialist is simplifying a bonus calculation formula: 50h + 50b. After factoring the expression as 50(h + b), the specialist wants to verify the result. According to the standard procedure for factoring the Greatest Common Factor (GCF), the specialist should check the work by distributing the 50 back through the parentheses to ensure the product matches the original formula.

A business analyst is following a standard four-step procedure to simplify a polynomial representing company overhead by factoring out the Greatest Common Factor (GCF). The analyst has already completed the first step by successfully identifying the GCF for all terms. According to the procedure, what is the next specific task the analyst must perform before they can apply the reverse Distributive Property to write the final factored form?

Procedural Steps for Factoring Overhead Costs

According to the standard four-step procedure for identifying the greatest common factor (GCF) of a polynomial, what is the technical name for this specific method of breaking down coefficients into their basic prime components?

Optimizing Assembly Line Output Formulas

A data analyst is simplifying a revenue calculation by identifying the greatest common factor (GCF) shared by all terms. This procedural step is mathematically defined as the reverse of __________ a polynomial by a monomial.

Imagine you are a senior analyst training a new team member on how to simplify complex resource allocation formulas. Write a brief instructional guide that lists and describes the four standard steps required to factor the Greatest Common Factor (GCF) from a polynomial expression. Your guide should explain the process from the initial identification of factors through to the final verification of the result.

Standard Operating Procedure for Factoring Shared Resource Costs

A production analyst is simplifying a formula to identify shared manufacturing costs across multiple assembly lines. According to the standard procedure for factoring the Greatest Common Factor (GCF) from a polynomial, which method is recommended to identify the largest expression that divides evenly into every term?

Factor $$8x^3y - 10x^2y^2 + 12xy^3$$ by extracting the greatest common factor.

**Step 1 — Find the GCF:** The three terms are $$8x^3y$$, $$-10x^2y^2$$, and $$12xy^3$$. The numerical GCF of $$8$$, $$-10$$, and $$12$$ is $$2$$. The shared variables are $$x$$ and $$y$$. The lowest power of $$x$$ is $$x^1$$ (or $$x$$), and the lowest power of $$y$$ is $$y^1$$ (or $$y$$). Therefore, the GCF is $$2xy$$.

**Step 2 — Rewrite each term using the GCF:** Express each term as the product of the GCF and the remaining factors:
$$2xy \cdot 4x^2 - 2xy \cdot 5xy + 2xy \cdot 6y^2$$

**Step 3 — Factor out the GCF:**
$$2xy(4x^2 - 5xy + 6y^2)$$

**Step 4 — Check by multiplying:**
$$2xy(4x^2 - 5xy + 6y^2) = 2xy \cdot 4x^2 - 2xy \cdot 5xy + 2xy \cdot 6y^2 = 8x^3y - 10x^2y^2 + 12xy^3$$ ✓

The factored form is $$2xy(4x^2 - 5xy + 6y^2)$$. This demonstrates how to factor polynomials with multiple variables by finding the GCF for each variable independently.

Factoring $$8x^3y - 10x^2y^2 + 12xy^3$$

Factor $$3y(y + 7) - 4(y + 7)$$ by identifying and extracting a **binomial** greatest common factor (GCF).

The expression consists of two terms: $$3y(y + 7)$$ and $$-4(y + 7)$$. Both terms share the common binomial factor $$(y + 7)$$, which serves as the GCF. Just as a monomial GCF is factored out using the reverse Distributive Property, a binomial GCF is factored out in the exact same way.

**Factor the GCF, $$(y + 7)$$:** Write the binomial GCF outside the parentheses and place the remaining factors — $$3y$$ and $$-4$$ — inside a second set of parentheses:
$$3y(y + 7) - 4(y + 7) = (y + 7)(3y - 4)$$

**Check by multiplying:** Distribute $$(y + 7)$$ back through $$(3y - 4)$$ to verify the result equals the original expression.

The factored form is $$(y + 7)(3y - 4)$$. This example demonstrates that the GCF of a polynomial does not have to be a monomial — it can be an entire binomial expression. Whenever every term of a polynomial contains the same binomial factor, that binomial can be factored out.

Factoring $$3y(y + 7) - 4(y + 7)$$

To completely factor a polynomial, follow a systematic three-step general strategy.

**Step 1.** Check for a Greatest Common Factor (GCF) among all terms and factor it out if one exists.

**Step 2.** Classify the polynomial by its number of terms to determine the appropriate factoring method:
*   **Binomials (two terms):** Check for special patterns. Is it a difference of squares? If so, factor it as the product of conjugates. Is it a sum or difference of cubes? Use the corresponding cube pattern. Note that a sum of squares cannot be factored over the real numbers.
*   **Trinomials (three terms):** If it has the form $$x^2 + bx + c$$, "undo FOIL" to find the binomial factors. If it has the form $$ax^2 + bx + c$$, first check if it fits the perfect square trinomial pattern where the first and last terms are perfect squares. If it does not, apply the trial and error method or the "ac" method.
*   **Polynomials with more than three terms:** Use the factoring by grouping method.

**Step 3.** Check the result. Verify that the polynomial is factored completely (meaning no factors can be broken down further) and multiply the factors together to ensure they produce the original polynomial.

Learn Before

Related