Chapter overview Maths

Types of numbers

Number calculations

Fractions, decimals and percentages

Algebraic manipulation

Formulae and equations

Straight line graphs

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Ratio

Proportion

Rates of change

Shapes

Properties of shapes

Measures

Lines and angles

Drawing shapes

Trigonometry

Probability

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Maths

# Algebraic notation 0%

Summary

# Algebraic notation

## In a nutshell

Algebra uses letters called 'variables' to represent unknown quantities. The basic rules for algebraic notation help write terms in a concise way. These terms can then be used in expressions, formulae or equations.

##### Example 1

The letter 'a' could represent an apple. Two apples could be described by $\underline{2a}$.​

## Basic rules

RULE

DESCRIPTION

EXAMPLE

Add the numbers and copy the variable. If there is no number with the variable, it means $1$​. For example, $x$​ means $1x$​​
$x+x=2x$​​

Subtract equal variables

Subtract the numbers and copy the variable.
$7x-5x=2x$​​

Multiply same variables

Multiplying the same variables changes the power. When multiplying add powers, if there is no number with the variable, it means $1$​.
$x \times x = x^2$​​

Multiply different variables

Write the letters without the multiplication sign.
Multiplying different variables will not change their powers.
$x \times y = xy$​​

## Formulae

Formulae help find quantities.

##### Examples
 ​$F=ma$​​ Calculate the force on an obejct from its mass and acceleration. ​$P = 2(l+w)$​​ Calculate the perimeter of a rectangle from its length and width. ​$A=\frac{1}{2} bh$​​ Calculate the area of a triangle from its base and its height.

## Equations

An equation is formed when two expressions equal each other.

##### Examples
 ​$\frac x 2 =5$​​ ​$2x-3=7$​​ ​$x^2 -2x-8=0$​​

FAQs

• Question: What is algebraic notation?

Answer: Algebraic notation involves writing algebraic terms, with a combination of numbers and letters. These terms can then be used further in expressions and equations.

• Question: What are variables?

Answer: Variables are a short hand way to name a quantity. The letter variable can then be used in an expression.

• Question: What is algebra?

Answer: Algebra uses letters called variables to represent unknown quantities.

Theory

Exercises