Factorisation Class 8 PPT

 Page 1


FACTORISATION
CLASS - 8
Page 2


FACTORISATION
CLASS - 8
PREVEIW
• PART1 FACTORS OF NATURAL NOS N ALGEBRAIC 
EXPNS
• PART2 METHOD OF COMMON FACTORS
• PART3 FACTORISATION BY REGROUPING TERMS 
• PART4 SOLVING SUMS ON FACTORIZING EXPNS
• PART5 SOLVING SUMS ON FACTORISATION 
USING IDEN
• PART6 FACTORS OF THE FORM (x+a)(x+b)
• PART7 DIVISION OF ALGEBRAIC EXPNS
• DOUBT s??????
Page 3


FACTORISATION
CLASS - 8
PREVEIW
• PART1 FACTORS OF NATURAL NOS N ALGEBRAIC 
EXPNS
• PART2 METHOD OF COMMON FACTORS
• PART3 FACTORISATION BY REGROUPING TERMS 
• PART4 SOLVING SUMS ON FACTORIZING EXPNS
• PART5 SOLVING SUMS ON FACTORISATION 
USING IDEN
• PART6 FACTORS OF THE FORM (x+a)(x+b)
• PART7 DIVISION OF ALGEBRAIC EXPNS
• DOUBT s??????
Introduction
Factors of natural numbers
e.g. 90 = 2 x 3 x 3 x 5
Factors of algebraic expressions
Terms are formed as product of factors.
e.g. 5xy = 5 x x x y
10x(x+2)(y+3)=2x5xxx(x+2)x(y+3)
Page 4


FACTORISATION
CLASS - 8
PREVEIW
• PART1 FACTORS OF NATURAL NOS N ALGEBRAIC 
EXPNS
• PART2 METHOD OF COMMON FACTORS
• PART3 FACTORISATION BY REGROUPING TERMS 
• PART4 SOLVING SUMS ON FACTORIZING EXPNS
• PART5 SOLVING SUMS ON FACTORISATION 
USING IDEN
• PART6 FACTORS OF THE FORM (x+a)(x+b)
• PART7 DIVISION OF ALGEBRAIC EXPNS
• DOUBT s??????
Introduction
Factors of natural numbers
e.g. 90 = 2 x 3 x 3 x 5
Factors of algebraic expressions
Terms are formed as product of factors.
e.g. 5xy = 5 x x x y
10x(x+2)(y+3)=2x5xxx(x+2)x(y+3)
Method of common factors
• We write each term as  a product of 
irreducible factors. Then take out the 
common factors of the terms and write the 
remaining factors to get the desired factor 
form.
• E.g. 5ab+10a
(5xaxb)+(10xa)
(5axb) + (5ax2)
5a( b+2 )    (desired factor form) 
Page 5


FACTORISATION
CLASS - 8
PREVEIW
• PART1 FACTORS OF NATURAL NOS N ALGEBRAIC 
EXPNS
• PART2 METHOD OF COMMON FACTORS
• PART3 FACTORISATION BY REGROUPING TERMS 
• PART4 SOLVING SUMS ON FACTORIZING EXPNS
• PART5 SOLVING SUMS ON FACTORISATION 
USING IDEN
• PART6 FACTORS OF THE FORM (x+a)(x+b)
• PART7 DIVISION OF ALGEBRAIC EXPNS
• DOUBT s??????
Introduction
Factors of natural numbers
e.g. 90 = 2 x 3 x 3 x 5
Factors of algebraic expressions
Terms are formed as product of factors.
e.g. 5xy = 5 x x x y
10x(x+2)(y+3)=2x5xxx(x+2)x(y+3)
Method of common factors
• We write each term as  a product of 
irreducible factors. Then take out the 
common factors of the terms and write the 
remaining factors to get the desired factor 
form.
• E.g. 5ab+10a
(5xaxb)+(10xa)
(5axb) + (5ax2)
5a( b+2 )    (desired factor form) 
Factorisation by regrouping terms
• Regrouping is re-arranging the terms with 
common terms.
e.g. 1) a
2
+ ab + 8a + 8b
a(a+b) + 8(a+b)
(a+b) (a+8)
2) 15ab – 6a + 5b – 2 
3a(5b-2) + 1(5b-2)
(3a+1) (5b-2)