Variables In Algebra

What is a variable?
A variable is something that can vary.
Examples of variables are:
The number of people in a bus.
The number of millemetres of rain in a day.
The number of correct answers in a test.


How do we show a variable?
We usually represent a variable by a letter.
We can use any letter
but x is the letter used very often.
Examples:
Let x be the number of people in a bus.
Let y be the number of millemetres of rain in a day.
Let z be the number of correct answers in a test.



Notice that we must be able to
count or measure a variable.

Examples:

We can count
the number of people in a bus.

We can measure
the number of millemetres of rain in a day.

We can count
the number of correct answers in a test.


TRUE OR FALSE

The number of apples in a box is a variable.
    

The height of a tree in metres is a variable.
    


QUESTIONS AND ANSWERS

Is the number of radios in a radio shop a variable?
Yes.
It makes sense to say:
Let x be the number of radios in a radio shop.

Is your age a variable?
Yes.
It makes sense to say:
Let x be the number of years of your age.



 
 

Start Algebra - Substitution

Start Algebra - One Step Equations

ALGEBRA INDEX


 
 







Start Algebra - Substitution

Start Algebra - One Step Equations

ALGEBRA INDEX


 
 


EXTERNAL LINK
Variable - Mathworld - Advanced





START Substitution In Algebra

START One Step Equations

ALGEBRA INDEX

EXTERNAL LINK
Variable - Mathworld - Advanced

 
Edited by Dr David Cornelius an Independent Private Maths Tutor with over 25 years of experience and The Secretary of The Association of Tutors in the UK for 15 years.