AlgebraKS3 / GCSE

Taking out a common numerical factor

Factorise by taking out the highest common numerical factor.

  • Find the highest common factor of all the coefficients.
  • Write this number outside one bracket and divide each term by it.
  • Keep the original signs inside the bracket, then check by expanding.

Example 1

Factorise fully. The highest common numerical factor is .

Use that factor in every term.

Example 2

Factorise fully. The highest common numerical factor is .

Use that factor in every term.

Remember
Factorising reverses expanding. Fully factorised means there is no further numerical factor shared by every term inside.

Your turn

Question 1

Factorise fully.

Check answer
The highest common numerical factor is .Use that factor in every term.
Question 2

Factorise fully.

Check answer
The highest common numerical factor is .Use that factor in every term.
Question 3

Factorise fully.

Check answer
The highest common numerical factor is .Use that factor in every term.
Question 4

Factorise fully.

Check answer
The highest common numerical factor is .Use that factor in every term.
Question 5

Factorise fully.

Check answer
The highest common numerical factor is .Use that factor in every term.
← All Algebra cardsReport a mistake

Related cards

Taking out a common algebraic factorExpanding a single bracket: using arrows