In algebra, we often get very long expressions that we need to make simpler. Simpler expressions are easier to solve.

To simplify an expression, we collect **like terms**.

Look at the expression: **4x + 5x -2 - 2x + 7**

To simplify:

- The x terms can be collected together to give 7x.
- The numbers can be collected together to give 5.

So 4x + 5x -2 - 2x + 7 simplified is 7x + 5.

Remember that terms are separated by + and - signs, and these are always attached to the front of a term.

- Question
Simplify this expression:

**x + 5 + 3x- 7 + 9x+ 3 - 4x**

- Answer
**To work it out:**- Write down the expression
- x + 5 + 3x - 7 + 9x + 3 - 4x

- Collect all the terms together which are alike. Remember that each term comes with an operation (+, -) which goes before it.
- x + 3x + 9x - 4x + 5 - 7 + 3

- Simplify the x terms.
- x + 3x + 9x - 4x = 9x

- Simplify the numbers separately.
- 5 - 7 + 3 = 1

**Answer:**x + 5 + 3x - 7 + 9x + 3 - 4x can be simplified to**9x + 1**

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

**This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.**