Algebra uses letters to represent unknown values.

​

Usually we use x, y to represent the variables, or any other letters.

​

When we multiply the variable by a number we don't use the multiplication sign to write it, for example:

2 × y = 2y

3 × z = 3z​

​

The same when we multiply two different variables:

y × z = yz​

​

TERM

A number or letter on its own, or numbers and letters multiplied together.

​

An expression is a string of terms combined using the operations +, – .​

​

An expression is a string of terms combined using the operations +, – .​

Algebraic terms that have the same letters are called like terms.

Only like terms can be added or subtracted.

When like terms are added and subtracted, it is called simplifying.

​

​

Write variable expressions for the following operations:

​

u multiplied by 8

​

​

​

t divides by 9

​

​

r multiplied by the sum of y and x​

​

​

​

Simplify :

​

3x + 7y + 10x - 2y =​

Multiply Terms:

​

​

Expanding brackets:

​

​Brackets are used in algebra to show a repeated calculation, without having to write the same calculation out several times.

Expanding brackets:

​

​