Skill: Factor a common numerical factor from an expression

Explanation and Free Practice Resources

Factoring a common numerical factor rewrites a sum or difference of terms as a product by applying the distributive property in reverse, such as 6x+15=3(2x+5)6x+15=3(2x+5). The factor must divide every term, and the remaining expression records each term’s quotient; choosing the greatest common numerical factor gives a useful simplest form and supports later work with equivalent expressions, equations, and polynomial factoring, without extending to advanced symbolic or multivariable cases.

Detailed Explanation: Factor a common numerical factor from an expression

To factor out a common numerical factor, find a number that divides every term. It is usually best to choose the greatest common factor (GCF).

Example: Factor 18x+2418x+24.

  1. Find the GCF of the numerical parts, 1818 and 2424:
GCF(18,24)=6\text{GCF}(18,24)=6
  1. Divide each term by 66:
18x÷6=3xand24÷6=418x\div 6=3x \qquad \text{and} \qquad 24\div 6=4
  1. Write 66 outside parentheses and the quotients inside:
18x+24=6(3x+4)18x+24=6(3x+4)
  1. Check by distributing 66:
6(3x+4)=6⋅3x+6⋅4=18x+246(3x+4)=6\cdot 3x+6\cdot 4=18x+24

Therefore, the factored form is

6(3x+4)\boxed{6(3x+4)}

The number outside the parentheses must divide every term in the original expression.

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Algebraic Functions - Remove Value From Bracketed Terms


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