PPT: Algebraic Expressions and Identities | Mathematics (Maths) Class 8 PDF Download

 Page 1


 ALGEBRAIC
EXPRESSIONS AND
IDENTITIES
Page 2


 ALGEBRAIC
EXPRESSIONS AND
IDENTITIES
a²
exponent
base number
Any mathematical expression which consists of
numbers, variables and operations are called Algebraic
Expression. 
What is an expression?
This tells us that a is multiplied
by itself two times.
So, a² means a x a
Page 3


 ALGEBRAIC
EXPRESSIONS AND
IDENTITIES
a²
exponent
base number
Any mathematical expression which consists of
numbers, variables and operations are called Algebraic
Expression. 
What is an expression?
This tells us that a is multiplied
by itself two times.
So, a² means a x a
Terms
Every expression is separated by an operation which is called Terms. Like 7n and 2
are the two terms in the above figure.
Factors
Every term is formed by the product of the factors.7n is the product of 7 and n
which are the factors of 7n.
Coefficient
The number placed before the variable or the numerical factor of the term is called
Coefficient of that variable.7 is the numerical factor of 7n so 7 is coefficient here.
Variable
Any letter like x, y etc. are called Variables. The variable in the above figure is n.
What are Terms , Factors and
Coefficients ?
Page 4


 ALGEBRAIC
EXPRESSIONS AND
IDENTITIES
a²
exponent
base number
Any mathematical expression which consists of
numbers, variables and operations are called Algebraic
Expression. 
What is an expression?
This tells us that a is multiplied
by itself two times.
So, a² means a x a
Terms
Every expression is separated by an operation which is called Terms. Like 7n and 2
are the two terms in the above figure.
Factors
Every term is formed by the product of the factors.7n is the product of 7 and n
which are the factors of 7n.
Coefficient
The number placed before the variable or the numerical factor of the term is called
Coefficient of that variable.7 is the numerical factor of 7n so 7 is coefficient here.
Variable
Any letter like x, y etc. are called Variables. The variable in the above figure is n.
What are Terms , Factors and
Coefficients ?
An expression can be represented on the number line.
Example : How to represent x + 5 and x – 5 on the number line?
Solution:
First, mark the distance x and then x + 5 will be 5 unit to the right of x.
In the case of x – 5 we will start from the right and move towards the negative side. x
– 5 will be 5 units to the left of x.
Number Line and an Expression
Page 5


 ALGEBRAIC
EXPRESSIONS AND
IDENTITIES
a²
exponent
base number
Any mathematical expression which consists of
numbers, variables and operations are called Algebraic
Expression. 
What is an expression?
This tells us that a is multiplied
by itself two times.
So, a² means a x a
Terms
Every expression is separated by an operation which is called Terms. Like 7n and 2
are the two terms in the above figure.
Factors
Every term is formed by the product of the factors.7n is the product of 7 and n
which are the factors of 7n.
Coefficient
The number placed before the variable or the numerical factor of the term is called
Coefficient of that variable.7 is the numerical factor of 7n so 7 is coefficient here.
Variable
Any letter like x, y etc. are called Variables. The variable in the above figure is n.
What are Terms , Factors and
Coefficients ?
An expression can be represented on the number line.
Example : How to represent x + 5 and x – 5 on the number line?
Solution:
First, mark the distance x and then x + 5 will be 5 unit to the right of x.
In the case of x – 5 we will start from the right and move towards the negative side. x
– 5 will be 5 units to the left of x.
Number Line and an Expression Monomials, Binomials and Polynomials
Expressions
Meaning
Example
M o n o m i a l
The algebraic expression having only
one term.
5x2
B i n o m i a l
Trinomial
The algebraic expression having two
terms.
The algebraic expression having three
terms.
The algebraic expression having one or
more terms with the variable having
non-negative integers as an exponent.
5x² + 2y
5x² + 2y + 9xy
5x² + 2y + 9xy + 4 and all
the above expressions are
also polynomial.
Polynomial