Factorise 5x − 20.

Step by step

The question

Question: factor 5x − 20.

Factor means: write it as a times, with brackets.

1 Take out the common factor

A term is one part between the + and − signs.

A common factor goes into every term.

5 goes into 20: 5 × 4 = 20.

So 5 goes into both.

So the common factor is 5.

We divide every term by it.

What is left goes in the bracket.

So it is 5(x − 4).

2 Check

Let's check: we multiply it back out.

The term in front times each part.

We get 5x − 20 again.

So 5(x − 4) is right!

Let's look back.

First: take out the common factor.

Last: check.