**Collecting Like Terms** *KS3 Revision*

## What you need to know

**Things to remember:**

- A term can come in three forms:

– A number by itself

– A letter by itself

– A combination of letters and numbers

- Like terms have the same combination of letters and numbers
- To add or subtract terms with the same letter, we add or subtract the numbers like usual and just put the letter back on the end.

*Collect the like terms in the following expression:*

4x+2x+3-x+1

Before we can answer this, we have to ask three questions:

- What is a term?
- What is a like term?
- How do we collect them?

Simply put, a term is a number by itself, a letter by itself, or a combination of numbers and letters.

So, now that we know what terms are, what are like terms?

Like terms can be number by themselves or terms with the same letters.

And finally, what does it mean to collect these like terms? This just means to do the additions and subtractions.

*Hint: **It is usually best to rewrite it with the like terms next to each other.*

And now you just need to do the additions and subtractions as usual.

4x+2x-x+3+1=5x+3

4x+2x+3-x+1=5x+3

A common mistake is to think that when you add algebraic terms together they will become squared, so try saying it like this: “I have four xs, I add two more to give me six, and then take one away. Now I have 5xs.”

Questions and expressions aren’t always linear, they could have powers like this:

They could also have more than one letter, like this:

They might even have these letters combined together, like this:

Finally, they might even have a combination of all of these!

## Example Questions

**Question 1:** Simplify the following expression by collection like terms:

5x+5-2x+3-4-x

5x+5-2x+3-4-x

5x-2x-x+5+3-4 = 2x+4[/latex

**Question 2:** Simplify the following expression by collection like terms:

ab+bc+2ab-bc+a

ab+bc+2ab-bc+a

ab+2ab+bc-bc+a = 3ab+a