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Maths

Maths

Algebraic notation

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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 2a\underline{2a}.​



Basic rules


RULE

DESCRIPTION

EXAMPLE

Add equal variables

Add the numbers and copy the variable. If there is no number with the variable, it means 11​. For example, xx​ means 1x1x​​
x+x=2xx+x=2x​​

Subtract equal variables

Subtract the numbers and copy the variable.
7x5x=2x7x-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 11​.
x×x=x2x \times x = x^2​​

Multiply different variables

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


Note: terms made of different variables cannot be added or subtracted.



Formulae

Formulae help find quantities.


Examples 
F=maF=ma​​
Calculate the force on an obejct from its mass and acceleration.
P=2(l+w)P = 2(l+w)​​
Calculate the perimeter of a rectangle from its length and width.
A=12bhA=\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
x2=5\frac x 2 =5 ​​
2x3=72x-3=7​​
x22x8=0x^2 -2x-8=0​​
Frequently Asked Questions (FAQ)

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

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