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NCERT Solutions for Class 8 Maths Chapter 14: Factorisation - Exercise 14.2

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NCERT Solutions for Class 8 Maths Chapter 14 (EX 14.2)

Free PDF download of NCERT Solutions for Class 8 Maths Chapter 14 Exercise 14.2 and all chapter exercises at one place prepared by expert teacher as per NCERT (CBSE) books guidelines. Class 8 Maths Chapter 14 Factorisation Exercise 14.2 Questions with Solutions to help you to revise complete Syllabus and Score More marks. Register and get all exercise solutions in your emails.Vedantu is a platform that provides free NCERT Solution and other study materials for students.


Class:

NCERT Solutions for Class 8

Subject:

Class 8 Maths

Chapter Name:

Chapter 14 - Factorisation

Exercise:

Exercise - 14.2

Content-Type:

Text, Videos, Images and PDF Format

Academic Year:

2024-25

Medium:

English and Hindi

Available Materials:

  • Chapter Wise

  • Exercise Wise

Other Materials

  • Important Questions

  • Revision Notes



Download NCERT Solution for Class 8 Maths to help you to revise complete syllabus ans score more marks in your examinations. also Students can download NCERT Solutions for Class 8 Science created by the best Teachers at Vedantu for Free.

Access NCERT Solutions for Class 8 Maths Chapter 14-Factorisation

Exercise 14.2

1. Factorise the following expression.

  1. Factorise the expression  $ {a^2} + 8a + 16 $ .

Ans: To factorise the expression  $ {a^2} + 8a + 16 $ write  $ {a^2} $ ,  $ 8a $  and 16 as a product of different numbers.

 $ {a^2} $ can be written as  $ {\left( a \right)^2} $ .

 $ 8a $ can be written as  $ 2 \times 4 \times a $ .

16 can be written as  $ {\left( 4 \right)^2} $ .

Substitute  $ {\left( a \right)^2} $ for  $ {a^2} $ ,  $ 2 \times 4 \times a $  for  $ 8a $  and  $ {\left( 4 \right)^2} $  for 16 in expression  $ {a^2} + 8a + 16 $ .

 $ {a^2} + 8a + 16 = {\left( a \right)^2} + 2 \times 4 \times a + {\left( 4 \right)^2} $ 

Simplify  $ {a^2} + 8a + 16 = {\left( a \right)^2} + 2 \times 4 \times a + {\left( 4 \right)^2} $ using algebraic identity  $ {\left( x \right)^2} + 2xy + {\left( y \right)^2} = {\left( {x + y} \right)^2} $ .

 $ {\left( a \right)^2} + 2 \times 4 \times a + {\left( 4 \right)^2} = {\left( {a + 4} \right)^2} $ 

Therefore  $ {a^2} + 8a + 16 $  can be factorized as  $ {\left( {a + 4} \right)^2} $ .


  1. Factorise the expression  $ {p^2} - 10p + 25 $ .

Ans: To factorise the expression  $ {p^2} - 10p + 25 $ write  $ {p^2} $ ,  $ 10p $  and 25 as a product of different numbers.

 $ {p^2} $ can be written as  $ {\left( p \right)^2} $ .

 $ 10p $ can be written as  $ 2 \times 5 \times p $ .

25 can be written as  $ {\left( 5 \right)^2} $ .

Substitute  $ {\left( p \right)^2} $ for  $ {p^2} $ ,  $ 2 \times 5 \times p $  for  $ 10p $  and  $ {\left( 5 \right)^2} $  for 25 in expression  $ {p^2} - 10p + 25 $ .

 $ {p^2} - 10p + 25 = {\left( p \right)^2} - 2 \times 5 \times p + {\left( 5 \right)^2} $ 

Simplify  $ {p^2} - 10p + 25 = {\left( p \right)^2} - 2 \times 5 \times p + {\left( 5 \right)^2} $ using algebraic identity  $ {\left( x \right)^2} - 2xy + {\left( y \right)^2} = {\left( {x - y} \right)^2} $ .

 $ {\left( p \right)^2} - 2 \times 5 \times p + {\left( 5 \right)^2} = {\left( {p - 5} \right)^2} $ 

Therefore  $ {p^2} - 10p + 25 $  can be factorized as  $ {\left( {p - 5} \right)^2} $ .


  1. Factorise the expression  $ 25{m^2} + 30m + 9 $ .

Ans: To factorise the expression  $ 25{m^2} + 30m + 9 $ write  $ 25{m^2} $ ,  $ 30m $  and 9 as a product of different numbers.

 $ 25{m^2} $ can be written as  $ {\left( {5m} \right)^2} $ .

 $ 30m $ can be written as  $ 2 \times 5m \times 3 $ .

9 can be written as  $ {\left( 3 \right)^2} $ .

Substitute  $ {\left( {5m} \right)^2} $ for  $ 25{m^2} $ ,  $ 2 \times 5m \times 3 $  for  $ 30m $  and  $ {\left( 3 \right)^2} $  for 9 in expression  $ 25{m^2} + 30m + 9 $ .

 $ 25{m^2} + 30m + 9 = {\left( {5m} \right)^2} + 2 \times 5m \times 3 + {\left( 3 \right)^2} $ 

Simplify  $ 25{m^2} + 30m + 9 = {\left( {5m} \right)^2} + 2 \times 5m \times 3 + {\left( 3 \right)^2} $ using algebraic identity  $ {\left( x \right)^2} + 2xy + {\left( y \right)^2} = {\left( {x + y} \right)^2} $ .

 $ {\left( {5m} \right)^2} + 2 \times 5m \times 3 + {\left( 3 \right)^2} = {\left( {5m + 3} \right)^2} $ 

Therefore  $ 25{m^2} + 30m + 9 $  can be factorized as  $ {\left( {5m + 3} \right)^2} $ .


  1. Factorise the expression  $ 49{y^2} + 84yz + 36{z^2} $ .

Ans: To factorise the expression  $ 49{y^2} + 84yz + 36{z^2} $ write  $ 49{y^2} $ ,  $ 84yz $  and  $ 36{z^2} $  as a product of different numbers.

 $ 49{y^2} $ can be written as  $ {\left( {7y} \right)^2} $ .

 $ 84yz $ can be written as  $ 2 \times 7y \times 6z $ .

 $ 36{z^2} $ can be written as  $ {\left( {6z} \right)^2} $ .

Substitute  $ {\left( {7y} \right)^2} $ for  $ 49{y^2} $ ,  $ 2 \times 7y \times 6z $  for  $ 84yz $  and  $ {\left( {6z} \right)^2} $  for  $ 36{z^2} $  in expression  $ 49{y^2} + 84yz + 36{z^2} $ .

 $ 49{y^2} + 84yz + 36{z^2} = {\left( {7y} \right)^2} + 2 \times 7y \times 6z + {\left( {6z} \right)^2} $ 

Simplify  $ 49{y^2} + 84yz + 36{z^2} = {\left( {7y} \right)^2} + 2 \times 7y \times 6z + {\left( {6z} \right)^2} $ using algebraic identity  $ {\left( x \right)^2} + 2xy + {\left( y \right)^2} = {\left( {x + y} \right)^2} $ .

 $ {\left( {7y} \right)^2} + 2 \times 7y \times 6z + {\left( {6z} \right)^2} = {\left( {7y + 6z} \right)^2} $ 

Therefore  $ 49{y^2} + 84yz + 36{z^2} $  can be factored as  $ {\left( {7y + 6z} \right)^2} $ .


  1. Factorise the expression  $ 4{x^2} - 8x + 4 $ .

Ans: To factorise the expression  $ 4{x^2} - 8x + 4 $ write  $ 4{x^2} $ ,  $ 8x $  and 4 as a product of different numbers.

 $ 4{x^2} $ can be written as  $ {\left( {2x} \right)^2} $ .

 $ 8x $ can be written as  $ 2 \times 2x \times 2 $ .

4 can be written as  $ {\left( 2 \right)^2} $ .

Substitute  $ {\left( {2x} \right)^2} $ for  $ 4{x^2} $ ,  $ 2 \times 2x \times 2 $  for  $ 8x $  and  $ {\left( 2 \right)^2} $  for 4 in expression  $ 4{x^2} - 8x + 4 $ .

 $ 4{x^2} - 8x + 4 = {\left( {2x} \right)^2} - 2 \times 2x \times 2 + {\left( 2 \right)^2} $ 

Simplify  $ 4{x^2} - 8x + 4 = {\left( {2x} \right)^2} - 2 \times 2x \times 2 + {\left( 2 \right)^2} $ using algebraic identity  $ {\left( x \right)^2} - 2xy + {\left( y \right)^2} = {\left( {x - y} \right)^2} $ .

 $ {\left( {2x} \right)^2} - 2 \times 2x \times 2 + {\left( 2 \right)^2} = {\left( {2x - 2} \right)^2} $ 

 $ {\left( {2x} \right)^2} - 2 \times 2x \times 2 + {\left( 2 \right)^2} = {\left[ {2\left( {x - 1} \right)} \right]^2} $ 

 $ {\left( {2x} \right)^2} - 2 \times 2x \times 2 + {\left( 2 \right)^2} = 4{\left( {x - 1} \right)^2} $ 

Therefore  $ 4{x^2} - 8x + 4 $  can be factorized as  $ 4{\left( {x - 1} \right)^2} $ .


  1. Factorise the expression  $ 121{b^2} - 88bc + 16{c^2} $ .

Ans: To factorise the expression  $ 121{b^2} - 88bc + 16{c^2} $ write  $ 121{b^2} $ ,  $ 88bc $  and  $ 16{c^2} $  as a product of different numbers.

 $ 121{b^2} $ can be written as  $ {\left( {11b} \right)^2} $ .

 $ 88bc $ can be written as  $ 2 \times 11b \times 4c $ .

 $ 16{c^2} $ can be written as  $ {\left( {4c} \right)^2} $ .

Substitute  $ {\left( {11b} \right)^2} $ for  $ 121{b^2} $ ,  $ 2 \times 11b \times 4c $  for  $ 88bc $  and  $ {\left( {4c} \right)^2} $  for  $ 16{c^2} $  in expression  $ 121{b^2} - 88bc + 16{c^2} $ .

 $ 121{b^2} - 88bc + 16{c^2} = {\left( {11b} \right)^2} - 2 \times 11b \times 4c + {\left( {4c} \right)^2} $ 

Simplify  $ 121{b^2} - 88bc + 16{c^2} = {\left( {11b} \right)^2} - 2 \times 11b \times 4c + {\left( {4c} \right)^2} $ using algebraic identity  $ {\left( x \right)^2} - 2xy + {\left( y \right)^2} = {\left( {x - y} \right)^2} $ .

 $ {\left( {11b} \right)^2} - 2 \times 11b \times 4c + {\left( {4c} \right)^2} = {\left( {11b - 4c} \right)^2} $ 

Therefore  $ 121{b^2} - 88bc + 16{c^2} $  can be factorized as  $ {\left( {11b - 4c} \right)^2} $ .


  1. Factorise the expression  $ {\left( {l + m} \right)^2} - 4lm $ .

Ans: To factorise the expression  $ {\left( {l + m} \right)^2} - 4lm $ expand  $ {\left( {l + m} \right)^2} $  using algebraic identity  $ {\left( {x + y} \right)^2} = {\left( x \right)^2} + 2xy + {\left( y \right)^2} $  and simplify.

 $ {\left( {l + m} \right)^2} = {\left( l \right)^2} + 2lm + {\left( m \right)^2} $ 

 $ {\left( {l + m} \right)^2} = {l^2} + 2lm + {m^2} $ 

Substitute  $ {l^2} + 2lm + {m^2} $  for  $ {\left( {l + m} \right)^2} $  in expression  $ {\left( {l + m} \right)^2} - 4lm $ and simplify.

 $ {\left( {l + m} \right)^2} - 4lm = {l^2} + 2lm + {m^2} - 4lm $ 

 $ {\left( {l + m} \right)^2} - 4lm = {l^2} - 2lm + {m^2} $ 

Now factorise $ {l^2} - 2lm + {m^2} $ .

 $ {l^2} $ can be written as  $ {\left( l \right)^2} $ .

 $ 2lm $ can be written as  $ 2 \times l \times m $ .

 $ {m^2} $ can be written as  $ {\left( m \right)^2} $ .

Substitute  $ {\left( l \right)^2} $ for  $ {l^2} $ ,  $ 2 \times l \times m $  for  $ 2lm $  and  $ {\left( m \right)^2} $  for  $ {m^2} $  in expression  $ {l^2} - 2lm + {m^2} $ .

 $ {l^2} - 2lm + {m^2} = {\left( l \right)^2} - 2 \times l \times m + {\left( m \right)^2} $ 

Simplify  $ {l^2} - 2lm + {m^2} = {\left( l \right)^2} - 2 \times l \times m + {\left( m \right)^2} $ using algebraic identity  $ {\left( x \right)^2} - 2xy + {\left( y \right)^2} = {\left( {x - y} \right)^2} $ .

 $ {\left( l \right)^2} - 2 \times l \times m + {\left( m \right)^2} = {\left( {l - m} \right)^2} $ 

Therefore  $ {\left( {l + m} \right)^2} - 4lm $  can be factorized as  $ {\left( {l - m} \right)^2} $ .


  1. Factorise the expression  $ {a^4} + 2{a^2}{b^2} + {b^4} $ .

Ans: To factorise the expression  $ {a^4} + 2{a^2}{b^2} + {b^4} $ write  $ {a^4} $ ,  $ 2{a^2}{b^2} $  and  $ {b^4} $  as a product of different numbers.

 $ {a^4} $ can be written as  $ {\left( {{a^2}} \right)^2} $ .

 $ 2{a^2}{b^2} $ can be written as  $ 2 \times {a^2} \times {b^2} $ .

 $ {b^4} $ can be written as  $ {\left( {{b^2}} \right)^2} $ .

Substitute  $ {\left( {{a^2}} \right)^2} $ for  $ {a^4} $ ,  $ 2 \times {a^2} \times {b^2} $  for  $ 2{a^2}{b^2} $  and  $ {\left( {{b^2}} \right)^2} $  for  $ {b^4} $  in expression  $ {a^4} + 2{a^2}{b^2} + {b^4} $ .

 $ {a^4} + 2{a^2}{b^2} + {b^4} = {\left( {{a^2}} \right)^2} + 2 \times {a^2} \times {b^2} + {\left( {{b^2}} \right)^2} $ 

Simplify  $ {a^4} + 2{a^2}{b^2} + {b^4} = {\left( {{a^2}} \right)^2} + 2 \times {a^2} \times {b^2} + {\left( {{b^2}} \right)^2} $ using algebraic identity  $ {\left( x \right)^2} + 2xy + {\left( y \right)^2} = {\left( {x + y} \right)^2} $ .

 $ {\left( {{a^2}} \right)^2} + 2 \times {a^2} \times {b^2} + {\left( {{b^2}} \right)^2} = {\left( {{a^2} + {b^2}} \right)^2} $ 

Therefore  $ {a^4} + 2{a^2}{b^2} + {b^4} $  can be factorized as  $ {\left( {{a^2} + {b^2}} \right)^2} $ .


2. Factorise the following expression.

  1. Factorise the expression  $ 4{p^2} - 9{q^2} $ .

Ans: To factorise $ 4{p^2} - 9{q^2} $ rewrite the expression as the square terms.

 $ 4{p^2} $ can be written as  $ {\left( {2p} \right)^2} $ .

 $ 9{q^2} $ can be written as  $ {\left( {3q} \right)^2} $ .

Substitute  $ {\left( {2p} \right)^2} $  for  $ 4{p^2} $  and  $ {\left( {3q} \right)^2} $  for  $ 9{q^2} $  in expression  $ 4{p^2} - 9{q^2} $ .

 $ 4{p^2} - 9{q^2} = {\left( {2p} \right)^2} - {\left( {3q} \right)^2} $ 

Simplify  $ 4{p^2} - 9{q^2} = {\left( {2p} \right)^2} - {\left( {3q} \right)^2} $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {\left( {2p} \right)^2} - {\left( {3q} \right)^2} = \left( {2p + 3q} \right)\left( {2p - 3q} \right) $ 

Therefore  $ 4{p^2} - 9{q^2} $  can be factorized as  $ \left( {2p + 3q} \right)\left( {2p - 3q} \right) $ .


  1. Factorise the expression  $ 63{a^2} - 112{b^2} $ .

Ans: To factorise $ 63{a^2} - 112{b^2} $ rewrite the expression as the square terms.

Take 7 as a common factor from expression  $ 63{a^2} - 112{b^2} $ .

 $ 63{a^2} - 112{b^2} = 7\left( {9{a^2} - 16{b^2}} \right) $ 

 $ 9{a^2} $ can be written as  $ {\left( {3a} \right)^2} $ .

 $ 16{b^2} $ can be written as  $ {\left( {4b} \right)^2} $ .

Substitute  $ {\left( {3a} \right)^2} $  for  $ 9{a^2} $  and  $ {\left( {4b} \right)^2} $  for  $ 16{b^2} $  in expression  $ 7\left( {9{a^2} - 16{b^2}} \right) $ .

 $ 7\left( {9{a^2} - 16{b^2}} \right) = 7\left[ {{{\left( {3a} \right)}^2} - {{\left( {4b} \right)}^2}} \right] $ 

Simplify  $ 7\left( {9{a^2} - 16{b^2}} \right) = 7\left[ {{{\left( {3a} \right)}^2} - {{\left( {4b} \right)}^2}} \right] $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ 7\left[ {{{\left( {3a} \right)}^2} - {{\left( {4b} \right)}^2}} \right] = 7\left( {3a + 4b} \right)\left( {3a - 4b} \right) $ 

Therefore  $ 63{a^2} - 112{b^2} $  can be factorized as  $ 7\left( {3a + 4b} \right)\left( {3a - 4b} \right) $ .


  1. Factorise the expression  $ 49{x^2} - 36 $ .

Ans: To factorise $ 49{x^2} - 36 $ rewrite the expression as the square terms.

 $ 49{x^2} $ can be written as  $ {\left( {7x} \right)^2} $ .

36 can be written as  $ {\left( 6 \right)^2} $ .

Substitute  $ {\left( {7x} \right)^2} $  for  $ 49{x^2} $  and  $ {\left( 6 \right)^2} $  for 36 in expression  $ 49{x^2} - 36 $ .

 $ 49{x^2} - 36 = {\left( {7x} \right)^2} - {\left( 6 \right)^2} $ 

Simplify  $ 49{x^2} - 36 = {\left( {7x} \right)^2} - {\left( 6 \right)^2} $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {\left( {7x} \right)^2} - {\left( 6 \right)^2} = \left( {7x + 6} \right)\left( {7x - 6} \right) $ 

Therefore  $ 49{x^2} - 36 $  can be factorized as  $ \left( {7x + 6} \right)\left( {7x - 6} \right) $ .


  1. Factorise the expression  $ 16{x^5} - 144{x^3} $ .

Ans: To factorise $ 16{x^5} - 144{x^3} $ rewrite the expression as the square terms.

Take  $ 16{x^3} $  as a common factor from the expression  $ 16{x^5} - 144{x^3} $ .

 $ 16{x^5} - 144{x^3} = 16{x^3}\left( {{x^2} - 9} \right) $ 

 $ {x^2} $ can be written as  $ {\left( x \right)^2} $ .

9 can be written as  $ {\left( 3 \right)^2} $ .

Substitute  $ {\left( x \right)^2} $  for  $ {x^2} $  and  $ {\left( 3 \right)^2} $  for 9 in expression  $ 16{x^3}\left( {{x^2} - 9} \right) $ .

 $ 16{x^3}\left( {{x^2} - 9} \right) = 16{x^3}\left[ {{{\left( x \right)}^2} - {{\left( 3 \right)}^2}} \right] $ 

Simplify  $ 16{x^3}\left( {{x^2} - 9} \right) = 16{x^3}\left[ {{{\left( x \right)}^2} - {{\left( 3 \right)}^2}} \right] $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ 16{x^3}\left[ {{{\left( x \right)}^2} - {{\left( 3 \right)}^2}} \right] = 16{x^3}\left( {x + 3} \right)\left( {x - 3} \right) $ 

Therefore  $ 16{x^5} - 144{x^3} $  can be factorized as  $ 16{x^3}\left( {x + 3} \right)\left( {x - 3} \right) $ .


  1. Factorise the expression  $ {\left( {l + m} \right)^2} - {\left( {l - m} \right)^2} $ .

Ans: To factorise $ {\left( {l + m} \right)^2} - {\left( {l - m} \right)^2} $ rewrite the expression as the square terms.

Simplify  $ {\left( {l + m} \right)^2} - {\left( {l - m} \right)^2} $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {\left( {l + m} \right)^2} - {\left( {l - m} \right)^2} = \left( {\left( {l + m} \right) + \left( {l - m} \right)} \right)\left( {\left( {l + m} \right) - \left( {l - m} \right)} \right) $ 

Simplify right hand side of expression  $ {\left( {l + m} \right)^2} - {\left( {l - m} \right)^2} = \left( {\left( {l + m} \right) + \left( {l - m} \right)} \right)\left( {\left( {l + m} \right) - \left( {l - m} \right)} \right) $ using addition.

 $ {\left( {l + m} \right)^2} - {\left( {l - m} \right)^2} = \left( {l + m + l - m} \right)\left( {l + m - l + m} \right) $ 

 $ {\left( {l + m} \right)^2} - {\left( {l - m} \right)^2} = 2l \cdot 2m $ 

 $ {\left( {l + m} \right)^2} - {\left( {l - m} \right)^2} = 4lm $ 

Therefore  $ {\left( {l + m} \right)^2} - {\left( {l - m} \right)^2} $  can be factorized as  $ 4lm $ .


  1. Factorise the expression  $ 9{x^2}{y^2} - 16 $ .

Ans: To factorise $ 9{x^2}{y^2} - 16 $ rewrite the expression as the square terms.

 $ 9{x^2}{y^2} $ can be written as  $ {\left( {3xy} \right)^2} $ .

16 can be written as  $ {\left( 4 \right)^2} $ .

Substitute  $ {\left( {3xy} \right)^2} $  for  $ 9{x^2}{y^2} $  and  $ {\left( 4 \right)^2} $  for 16 in expression  $ 9{x^2}{y^2} - 16 $ .

 $ 9{x^2}{y^2} - 16 = {\left( {3xy} \right)^2} - {\left( 4 \right)^2} $ 

Simplify  $ 9{x^2}{y^2} - 16 = {\left( {3xy} \right)^2} - {\left( 4 \right)^2} $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {\left( {3xy} \right)^2} - {\left( 4 \right)^2} = \left( {3xy + 4} \right)\left( {3xy - 4} \right) $ 

Therefore  $ 9{x^2}{y^2} - 16 $  can be factorized as  $ \left( {3xy + 4} \right)\left( {3xy - 4} \right) $ .


  1. Factorise the expression  $ \left( {{x^2} - 2xy + {y^2}} \right) - {z^2} $

Ans: To factorise $ \left( {{x^2} - 2xy + {y^2}} \right) - {z^2} $ rewrite the expression as the square terms.

 $ \left( {{x^2} - 2xy + {y^2}} \right) $ can be written as  $ {\left( {x - y} \right)^2} $  using algebraic identity  $ {\left( x \right)^2} - 2xy + {\left( y \right)^2} = {\left( {x - y} \right)^2} $ .

 $ {z^2} $ can be written as  $ {\left( z \right)^2} $ .

Substitute  $ {\left( {x - y} \right)^2} $  for  $ \left( {{x^2} - 2xy + {y^2}} \right) $  and  $ {\left( z \right)^2} $  for  $ {z^2} $  in expression  $ \left( {{x^2} - 2xy + {y^2}} \right) - {z^2} $ .

 $ \left( {{x^2} - 2xy + {y^2}} \right) - {z^2} = {\left( {x - y} \right)^2} - {\left( z \right)^2} $ 

Simplify  $ \left( {{x^2} - 2xy + {y^2}} \right) - {z^2} = {\left( {x - y} \right)^2} - {\left( z \right)^2} $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {\left( {x - y} \right)^2} - {\left( z \right)^2} = \left( {x - y + z} \right)\left( {x - y - z} \right) $ 

Therefore  $ \left( {{x^2} - 2xy + {y^2}} \right) - {z^2} $  can be factorized as  $ \left( {x - y + z} \right)\left( {x - y - z} \right) $ .


  1. Factorise the expression  $ 25{a^2} - 4{b^2} + 28bc - 49{c^2} $ .

Ans: To factorise $ 25{a^2} - 4{b^2} + 28bc - 49{c^2} $ rewrite the expression as the square terms.

Rewrite  $ 25{a^2} - 4{b^2} + 28bc - 49{c^2} $ as  $ 25{a^2} - \left( {4{b^2} - 28bc + 49{c^2}} \right) $ .

 $ \left( {4{b^2} - 28bc + 49{c^2}} \right) $ can be written as  $ {\left( {2b - 7c} \right)^2} $  using algebraic identity  $ {\left( x \right)^2} - 2xy + {\left( y \right)^2} = {\left( {x - y} \right)^2} $ .

 $ 25{a^2} $ can be written as  $ {\left( {5a} \right)^2} $ .

Substitute  $ {\left( {2b - 7c} \right)^2} $  for  $ \left( {4{b^2} - 28bc + 49{c^2}} \right) $  and  $ {\left( {5a} \right)^2} $  for  $ 25{a^2} $  in expression  $ 25{a^2} - \left( {4{b^2} - 28bc + 49{c^2}} \right) $ .

 $ 25{a^2} - \left( {4{b^2} - 28bc + 49{c^2}} \right) = {\left( {5a} \right)^2} - {\left( {2b - 7c} \right)^2} $ 

Simplify  $ 25{a^2} - \left( {4{b^2} - 28bc + 49{c^2}} \right) = {\left( {5a} \right)^2} - {\left( {2b - 7c} \right)^2} $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {\left( {5a} \right)^2} - {\left( {2b - 7c} \right)^2} = \left( {5a + 2b - 7c} \right)\left( {5a - 2b + 7c} \right) $ 

Therefore  $ 25{a^2} - 4{b^2} + 28bc - 49{c^2} $  can be factorized as  $ \left( {5a + 2b - 7c} \right)\left( {5a - 2b + 7c} \right) $ .


3. Factorise the expressions.

  1. Factorise the expression  $ a{x^2} + bx $ .

Ans: To factorise the expression  $ a{x^2} + bx $ write  $ a{x^2} $  and  $ bx $  as a product.

 $ a{x^2} $ can be written as  $ a \times x \times x $ .

 $ bx $ can be written as  $ b \times x $ .

Substitute  $ a \times x \times x $  for  $ a{x^2} $  and  $ b \times x $  for  $ bx $  in expression  $ a{x^2} + bx $ .

 $ a{x^2} + bx = \left( {a \times x \times x} \right) + \left( {b \times x} \right) $ 

Take  $ x $  as a common factor from right hand side of expression  $ a{x^2} + bx = \left( {a \times x \times x} \right) + \left( {b \times x} \right) $ .

 $ a{x^2} + bx = x\left[ {\left( {a \times x} \right) + \left( b \right)} \right] $ 

 $ a{x^2} + bx = x\left( {ax + b} \right) $ 

Therefore  $ a{x^2} + bx $  can be factorized as  $ x\left( {ax + b} \right) $ .


  1. Factorise the expression  $ 7{p^2} + 21{q^2} $ .

Ans: To factorise the expression  $ 7{p^2} + 21{q^2} $ write  $ 7{p^2} $  and  $ 21{q^2} $  as a product.

 $ 7{p^2} $ can be written as  $ 7 \times p \times p $ .

 $ 21{q^2} $ can be written as  $ 3 \times 7 \times q \times q $ .

Substitute  $ 7 \times p \times p $  for  $ 7{p^2} $  and  $ 3 \times 7 \times q \times q $  for  $ 21{q^2} $  in expression  $ 7{p^2} + 21{q^2} $ .

 $ 7{p^2} + 21{q^2} = \left( {7 \times p \times p} \right) + \left( {3 \times 7 \times q \times q} \right) $ 

Take 7 as a common factor from right hand side of expression  $ 7{p^2} + 21{q^2} = \left( {7 \times p \times p} \right) + \left( {3 \times 7 \times q \times q} \right) $ .

 $ 7{p^2} + 21{q^2} = 7\left[ {\left( {p \times p} \right) + \left( {3 \times q \times q} \right)} \right] $ 

 $ 7{p^2} + 21{q^2} = 7\left( {{p^2} + 3{q^2}} \right) $ 

Therefore  $ 7{p^2} + 21{q^2} $  can be factorized as  $ 7\left( {{p^2} + 3{q^2}} \right) $ .


  1.  Factorise the expression  $ 2{x^3} + 2x{y^2} + 2x{z^2} $ .

Ans: To factorise the expression  $ 2{x^3} + 2x{y^2} + 2x{z^2} $ write  $ 2{x^3} $ ,  $ 2x{y^2} $  and  $ 2x{z^2} $  as a product.

 $ 2{x^3} $ can be written as  $ 2 \times x \times x \times x $ .

 $ 2x{y^2} $ can be written as  $ 2 \times x \times y \times y $ .

 $ 2x{z^2} $ can be written as  $ 2 \times x \times z \times z $ .

Substitute  $ 2 \times x \times x \times x $ for  $ 2{x^3} $ ,  $ 2 \times x \times y \times y $  for  $ 2x{y^2} $  and  $ 2 \times x \times z \times z $  for  $ 2x{z^2} $  in expression  $ 2{x^3} + 2x{y^2} + 2x{z^2} $ .

 $ 2{x^3} + 2x{y^2} + 2x{z^2} = \left( {2 \times x \times x \times x} \right) + \left( {2 \times x \times y \times y} \right) + \left( {2 \times x \times z \times z} \right) $ 

Take  $ 2x $  as a common factor from right hand side of expression  $ 2{x^3} + 2x{y^2} + 2x{z^2} = \left( {2 \times x \times x \times x} \right) + \left( {2 \times x \times y \times y} \right) + \left( {2 \times x \times z \times z} \right) $ .

 $ 2{x^3} + 2x{y^2} + 2x{z^2} = 2x\left[ {\left( {x \times x} \right) + \left( {y \times y} \right) + \left( {z \times z} \right)} \right] $ 

 $ 2{x^3} + 2x{y^2} + 2x{z^2} = 2x\left( {{x^2} + {y^2} + {z^2}} \right) $ 

Therefore  $ 2{x^3} + 2x{y^2} + 2x{z^2} $  can be factorized as  $ 2x\left( {{x^2} + {y^2} + {z^2}} \right) $ .


  1.  Factorise the expression  $ a{m^2} + b{m^2} + a{n^2} + b{n^2} $ .

Ans: To factorise the expression  $ a{m^2} + b{m^2} + a{n^2} + b{n^2} $ write  $ a{m^2} $ ,  $ b{m^2} $ ,  $ a{n^2} $  and  $ b{n^2} $  as a product.

 $ a{m^2} $ can be written as  $ a \times m \times m $ .

 $ b{m^2} $ can be written as  $ b \times m \times m $ .

 $ a{n^2} $ can be written as  $ a \times n \times n $ .

 $ b{n^2} $ can be written as  $ b \times n \times n $ .

Thus expression formed is  $ a{m^2} + b{m^2} + a{n^2} + b{n^2} = \left( {a \times m \times m} \right) + \left( {b \times m \times m} \right) + \left( {a \times n \times n} \right) + \left( {b \times n \times n} \right) $ 

Take  $ {m^2} $  as a common factor from  $ a \times m \times m $ ,  $ b \times m \times m $  and  $ {n^2} $  as a common factor from  $ a \times n \times n $ ,  $ b \times n \times n $  from right hand side of expression  $ a{m^2} + b{m^2} + a{n^2} + b{n^2} = \left( {a \times m \times m} \right) + \left( {b \times m \times m} \right) + \left( {a \times n \times n} \right) + \left( {b \times n \times n} \right) $ .

 $ a{m^2} + b{m^2} + a{n^2} + b{n^2} = {m^2}\left[ {\left( a \right) + \left( b \right)} \right] + {n^2}\left[ {\left( a \right) + \left( b \right)} \right] $ 

 $ a{m^2} + b{m^2} + a{n^2} + b{n^2} = {m^2}\left( {a + b} \right) + {n^2}\left( {a + b} \right) $ 

 $ a{m^2} + b{m^2} + a{n^2} + b{n^2} = \left( {a + b} \right)\left( {{m^2} + {n^2}} \right) $ 

Therefore  $ a{m^2} + b{m^2} + a{n^2} + b{n^2} $  can be factorized as  $ \left( {a + b} \right)\left( {{m^2} + {n^2}} \right) $ .


  1. Factorise the expression  $ \left( {lm + l} \right) + m + 1 $ .

Ans: To factorise the expression  $ \left( {lm + l} \right) + m + 1 $ take  $ l $  as a common factor from  $ \left( {lm + l} \right) $  and simplify.

 $ \left( {lm + l} \right) + m + 1 = l\left( {m + 1} \right) + \left( {m + 1} \right) $ 

 $ \left( {lm + l} \right) + m + 1 = \left( {l + 1} \right)\left( {m + 1} \right) $ 

Therefore  $ \left( {lm + l} \right) + m + 1 $  can be factorized as  $ \left( {l + 1} \right)\left( {m + 1} \right) $ .


  1. Factorise the expression  $ y\left( {y + z} \right) + 9\left( {y + z} \right) $ .

Ans: To factorise the expression  $ y\left( {y + z} \right) + 9\left( {y + z} \right) $ take  $ \left( {y + z} \right) $  as a common factor from the expression and simplify.

 $ y\left( {y + z} \right) + 9\left( {y + z} \right) = \left( {y + z} \right)\left( {y + 9} \right) $ 

Therefore  $ y\left( {y + z} \right) + 9\left( {y + z} \right) $  can be factorized as  $ \left( {y + z} \right)\left( {y + 9} \right) $ .


  1. Factorise the expression  $ 5{y^2} - 20y - 8z + 2yz $ .

Ans: To factorise the expression  $ 5{y^2} - 20y - 8z + 2yz $ take  $ 5y $  as a common factor from  $ 5{y^2} $ ,  $ 20y $  and  $ 2z $  as a common factor from  $  - 8z $ ,  $ 2yz $  from the expression  $ 5{y^2} - 20y - 8z + 2yz $ and simplify.

 $ 5{y^2} - 20y - 8z + 2yz = 5y\left( {y - 4} \right) + 2z\left( { - 4 + y} \right) $ 

 $ 5{y^2} - 20y - 8z + 2yz = 5y\left( {y - 4} \right) + 2z\left( {y - 4} \right) $ 

 $ 5{y^2} - 20y - 8z + 2yz = \left( {y - 4} \right)\left( {5y + 2z} \right) $ 

Therefore  $ 5{y^2} - 20y - 8z + 2yz $  can be factorized as  $ \left( {y - 4} \right)\left( {5y + 2z} \right) $ .


  1. Factorise the expression  $ 10ab + 4a + 5b + 2 $ .

Ans: To factorise the expression  $ 10ab + 4a + 5b + 2 $ take  $ 2a $  as a common factor from  $ 10ab $ ,  $ 4a $  and 1 as a common factor from  $ 5b $ , 2 from the expression  $ 10ab + 4a + 5b + 2 $ and simplify.

 $ 10ab + 4a + 5b + 2 = 2a\left( {5b + 2} \right) + 1\left( {5b + 2} \right) $ 

 $ 10ab + 4a + 5b + 2 = \left( {5b + 2} \right)\left( {2a + 1} \right) $ 

Therefore  $ 10ab + 4a + 5b + 2 $  can be factorized as  $ \left( {5b + 2} \right)\left( {2a + 1} \right) $ .


  1. Factorise the expression  $ 6xy - 4y + 6 - 9x $ .

Ans: To factorise the expression  $ 6xy - 4y + 6 - 9x $ take  $ 2y $  as a common factor from  $ 6xy $ ,  $ 4y $  and 3 as a common factor from  $ 9x $ , 6 from the expression  $ 6xy - 4y + 6 - 9x $ and simplify.

 $ 6xy - 4y + 6 - 9x = 2y\left( {3x - 2} \right) + 3\left( {2 - 3x} \right) $ 

 $ 6xy - 4y + 6 - 9x = 2y\left( {3x - 2} \right) - 3\left( {3x - 2} \right) $ 

 $ 6xy - 4y + 6 - 9x = \left( {3x - 2} \right)\left( {2y - 3} \right) $ 

Therefore  $ 6xy - 4y + 6 - 9x $  can be factorized as  $ \left( {3x - 2} \right)\left( {2y - 3} \right) $ .


4. Factorise the following.

  1. Factorise the expression  $ {a^4} - {b^4} $ .

Ans: To factorise $ {a^4} - {b^4} $ rewrite the expression as the square terms.

 $ {a^4} $ can be written as  $ {\left( {{a^2}} \right)^2} $ .

 $ {b^4} $ can be written as  $ {\left( {{b^2}} \right)^2} $ .

Substitute  $ {\left( {{a^2}} \right)^2} $  for  $ {a^4} $  and  $ {\left( {{b^2}} \right)^2} $  for  $ {b^4} $  in expression  $ {a^4} - {b^4} $ .

 $ {a^4} - {b^4} = {\left( {{a^2}} \right)^2} - {\left( {{b^2}} \right)^2} $ 

Simplify  $ {a^4} - {b^4} = {\left( {{a^2}} \right)^2} - {\left( {{b^2}} \right)^2} $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {\left( {{a^2}} \right)^2} - {\left( {{b^2}} \right)^2} = \left( {{a^2} + {b^2}} \right)\left( {{a^2} - {b^2}} \right) $ 

Again simplify  $ \left( {{a^2} - {b^2}} \right) $  using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {\left( {{a^2}} \right)^2} - {\left( {{b^2}} \right)^2} = \left( {{a^2} + {b^2}} \right)\left( {a - b} \right)\left( {a + b} \right) $ 

Therefore  $ {a^4} - {b^4} $  can be factorized as  $ \left( {{a^2} + {b^2}} \right)\left( {a - b} \right)\left( {a + b} \right) $ .


  1. Factorise the expression  $ {p^4} - 81 $ .

Ans: To factorise $ {p^4} - 81 $ rewrite the expression as the square terms.

 $ {p^4} $ can be written as  $ {\left( {{p^2}} \right)^2} $ .

81 can be written as  $ {\left( {{3^2}} \right)^2} $ .

Substitute  $ {\left( {{p^2}} \right)^2} $  for  $ {p^4} $  and  $ {\left( {{3^2}} \right)^2} $  for 81 in expression  $ {p^4} - 81 $ .

 $ {p^4} - 81 = {\left( {{p^2}} \right)^2} - {\left( {{3^2}} \right)^2} $ 

Simplify  $ {p^4} - 81 = {\left( {{p^2}} \right)^2} - {\left( {{3^2}} \right)^2} $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {\left( {{p^2}} \right)^2} - {\left( {{3^2}} \right)^2} = \left( {{p^2} + {3^2}} \right)\left( {{p^2} - {3^2}} \right) $ 

Again simplify  $ \left( {{p^2} - {3^2}} \right) $  using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {\left( {{p^2}} \right)^2} - {\left( {{3^2}} \right)^2} = \left( {{p^2} + {3^2}} \right)\left( {p - 3} \right)\left( {p + 3} \right) $ 

 $ {p^4} - 81 = \left( {{p^2} + 9} \right)\left( {p - 3} \right)\left( {p + 3} \right) $ 

Therefore  $ {p^4} - 81 $  can be factorized as  $ \left( {{p^2} + 9} \right)\left( {p - 3} \right)\left( {p + 3} \right) $ .


  1. Factorise the expression  $ {x^4} - {\left( {y + z} \right)^4} $ .

Ans: To factorise $ {x^4} - {\left( {y + z} \right)^4} $ rewrite the expression as the square terms.

 $ {x^4} $ can be written as  $ {\left( {{x^2}} \right)^2} $ .

 $ {\left( {y + z} \right)^4} $ can be written as  $ {\left( {{{\left( {y + z} \right)}^2}} \right)^2} $ .

Substitute  $ {\left( {{x^2}} \right)^2} $  for  $ {x^4} $  and  $ {\left( {{{\left( {y + z} \right)}^2}} \right)^2} $  for  $ {\left( {y + z} \right)^4} $  in expression  $ {x^4} - {\left( {y + z} \right)^4} $ .

 $ {x^4} - {\left( {y + z} \right)^4} = {\left( {{x^2}} \right)^2} - {\left( {{{\left( {y + z} \right)}^2}} \right)^2} $ 

Simplify  $ {x^4} - {\left( {y + z} \right)^4} = {\left( {{x^2}} \right)^2} - {\left( {{{\left( {y + z} \right)}^2}} \right)^2} $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {x^4} - {\left( {y + z} \right)^4} = \left( {{x^2} + {{\left( {y + z} \right)}^2}} \right)\left( {{x^2} - {{\left( {y + z} \right)}^2}} \right) $ 

Again simplify  $ \left( {{x^2} - {{\left( {y + z} \right)}^2}} \right) $  using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {x^4} - {\left( {y + z} \right)^4} = \left( {{x^2} + {{\left( {y + z} \right)}^2}} \right)\left( {x - \left( {y + z} \right)} \right)\left( {x + \left( {y + z} \right)} \right) $ 

 $ {x^4} - {\left( {y + z} \right)^4} = \left( {{x^2} + {{\left( {y + z} \right)}^2}} \right)\left( {x - y - z} \right)\left( {x + y + z} \right) $ 

Therefore  $ {x^4} - {\left( {y + z} \right)^4} $  can be factorized as  $ \left( {{x^2} + {{\left( {y + z} \right)}^2}} \right)\left( {x - y - z} \right)\left( {x + y + z} \right) $ .


  1. Factorise the expression  $ {x^4} - {\left( {x - z} \right)^4} $ .

Ans: To factorise $ {x^4} - {\left( {x - z} \right)^4} $ rewrite the expression as the square terms.

 $ {x^4} $ can be written as  $ {\left( {{x^2}} \right)^2} $ .

 $ {\left( {x - z} \right)^4} $ can be written as  $ {\left( {{{\left( {x - z} \right)}^2}} \right)^2} $ .

Substitute  $ {\left( {{x^2}} \right)^2} $  for  $ {x^4} $  and  $ {\left( {{{\left( {x - z} \right)}^2}} \right)^2} $  for  $ {\left( {x - z} \right)^4} $  in expression  $ {x^4} - {\left( {x - z} \right)^4} $ .

 $ {x^4} - {\left( {x - z} \right)^4} = {\left( {{x^2}} \right)^2} - {\left( {{{\left( {x - z} \right)}^2}} \right)^2} $ 

Simplify  $ {x^4} - {\left( {x - z} \right)^4} = {\left( {{x^2}} \right)^2} - {\left( {{{\left( {x - z} \right)}^2}} \right)^2} $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {x^4} - {\left( {x - z} \right)^4} = \left( {{x^2} + {{\left( {x - z} \right)}^2}} \right)\left( {{x^2} - {{\left( {x - z} \right)}^2}} \right) $ 

Again simplify  $ \left( {{x^2} - {{\left( {x - z} \right)}^2}} \right) $  using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {x^4} - {\left( {x - z} \right)^4} = \left( {{x^2} + {{\left( {x - z} \right)}^2}} \right)\left( {x - \left( {x - z} \right)} \right)\left( {x + \left( {x - z} \right)} \right) $ 

 $ {x^4} - {\left( {x - z} \right)^4} = \left( {{x^2} + {x^2} - 2xz + {z^2}} \right)\left( z \right)\left( {2x - z} \right) $ 

 $ {x^4} - {\left( {x - z} \right)^4} = z\left( {2{x^2} - 2xz + {z^2}} \right)\left( {2x - z} \right) $ 

Therefore  $ {x^4} - {\left( {x - z} \right)^4} $  can be factorized as  $ z\left( {2{x^2} - 2xz + {z^2}} \right)\left( {2x - z} \right) $ .


  1. Factorise the expression  $ {a^4} - 2{a^2}{b^2} + {b^4} $ .

Ans: To factorise $ {a^4} - 2{a^2}{b^2} + {b^4} $ rewrite the expression as the square terms.

Rewrite  $ {a^4} - 2{a^2}{b^2} + {b^4} $ as  $ {\left( {{a^2}} \right)^2} - \left( {2{a^2}{b^2}} \right) + {\left( {{b^2}} \right)^2} $ .

$ {\left( {{a^2}} \right)^2} - \left( {2{a^2}{b^2}} \right) + {\left( {{b^2}} \right)^2} $ can be written as  $ {\left( {{a^2} - {b^2}} \right)^2} $  using algebraic identity  $ {\left( x \right)^2} - 2xy + {\left( y \right)^2} = {\left( {x - y} \right)^2} $ .

Simplify  $ {a^4} - 2{a^2}{b^2} + {b^4} = {\left( {{a^2} - {b^2}} \right)^2} $ using algebraic identity  $ {x^2} - {y^2} = \left( {x + y} \right)\left( {x - y} \right) $ .

 $ {a^4} - 2{a^2}{b^2} + {b^4} = {\left[ {\left( {a - b} \right)\left( {a + b} \right)} \right]^2} $ 

 $ {a^4} - 2{a^2}{b^2} + {b^4} = {\left( {a - b} \right)^2}{\left( {a + b} \right)^2} $ 

Therefore  $ {a^4} - 2{a^2}{b^2} + {b^4} $  can be factorized as  $ {\left( {a - b} \right)^2}{\left( {a + b} \right)^2} $ .


5. Factorise the following.

  1. Factorise the expression  $ {p^2} + 6p + 8 $ .

Ans: To factorise $ {p^2} + 6p + 8 $ , split the middle term such that the product of terms is equal to the product of the first term and the last term of expression and the sum is equal to the middle term of expression.

Write  $ 6p $  as  $ 4p + 2p $  because  $ 4p + 2p $  gives  $ 6p $  and  $ 4p \times 2p $ gives  $ 8{p^2} $ .

 $ {p^2} + 6p + 8 = {p^2} + 4p + 2p + 8 $ 

Take  $ p $  as a common factor from  $ {p^2} $ ,  $ 4p $  and 2 as a common factor from  $ 2p $ , 8 in expression  $ {p^2} + 6p + 8 = {p^2} + 4p + 2p + 8 $ and simplify.

 $ {p^2} + 4p + 2p + 8 = p\left( {p + 4} \right) + 2\left( {p + 4} \right) $ 

 $ {p^2} + 6p + 8 = \left( {p + 4} \right)\left( {p + 2} \right) $ 

Therefore  $ {p^2} + 6p + 8 $ can be factorized as  $ \left( {p + 4} \right)\left( {p + 2} \right) $ .


  1. Factorise the expression  $ {q^2} - 10q + 21 $ .

Ans: To factorise $ {q^2} - 10q + 21 $ split the middle term such that the product of terms is equal to the product of the first term and the last term of expression and the sum is equal to the middle term of expression.

Write  $  - 10q $  as  $  - 7q - 3q $  because  $  - 7q - 3q $  gives  $  - 10q $  and  $ \left( { - 7q} \right) \times \left( { - 3q} \right) $ gives  $ 21{q^2} $ .

 $ {q^2} - 10q + 21 = {q^2} - 7q - 3q + 21 $ 

Take  $ q $  as a common factor from  $ {q^2} $ ,  $ 7q $  and  $  - 3 $  as a common factor from  $  - 3q $ , 21 in expression  $ {q^2} - 10q + 21 = {q^2} - 7q - 3q + 21 $ and simplify.

 $ {q^2} - 7q - 3q + 21 = q\left( {q - 7} \right) - 3\left( {q - 7} \right) $ 

 $ {q^2} - 10q + 21 = \left( {q - 7} \right)\left( {q - 3} \right) $ 

Therefore  $ {q^2} - 10q + 21 $ can be factorized as  $ \left( {q - 7} \right)\left( {q - 3} \right) $ .


  1. Factorise the expression  $ {p^2} + 6p - 16 $ .

Ans: To factorise $ {p^2} + 6p - 16 $ split the middle term such that the product of terms is equal to the product of the first term and the last term of expression and the sum is equal to the middle term of expression.

Write  $ 6p $  as  $ 8p - 2p $  because  $ 8p - 2p $  gives  $ 6p $  and  $ 8p \times \left( { - 2p} \right) $ gives  $  - 16{p^2} $ .

 $ {p^2} + 6p - 16 = {p^2} + 8p - 2p - 16 $ 

Take  $ p $  as a common factor from  $ {p^2} $ ,  $ 8p $  and  $  - 2 $  as a common factor from  $  - 2p $ ,  $  - 16 $  in expression  $ {p^2} + 6p - 16 = {p^2} + 8p - 2p - 16 $ and simplify.

 $ {p^2} + 8p - 2p - 16 = p\left( {p + 8} \right) - 2\left( {p + 8} \right) $ 

 $ {p^2} + 6p - 16 = \left( {p + 8} \right)\left( {p - 2} \right) $ 

Therefore  $ {p^2} + 6p - 16 $ can be factorized as  $ \left( {p + 8} \right)\left( {p - 2} \right) $ .


NCERT Solutions for Class 8 Maths Chapter 14 Factorisation Exercise 14.2

Opting for the NCERT solutions for Ex 14.2 Class 8 Maths is considered as the best option for the CBSE students when it comes to exam preparation. This chapter consists of many exercises. Out of which we have provided the Exercise 14.2 Class 8 Maths NCERT solutions on this page in PDF format. You can download this solution as per your convenience or you can study it directly from our website/ app online.

Vedantu in-house subject matter experts have solved the problems/ questions from the exercise with the utmost care and by following all the guidelines by CBSE. Class 8 students who are thorough with all the concepts from the Subject Factorisation textbook and quite well-versed with all the problems from the exercises given in it, then any student can easily score the highest possible marks in the final exam. With the help of this Class 8 Maths Chapter 14 Exercise 14.2 solutions, students can easily understand the pattern of questions that can be asked in the exam from this chapter and also learn the marks weightage of the chapter. So that they can prepare themselves accordingly for the final exam.

Besides these NCERT solutions for Class 8 Maths Chapter 14 Exercise 14.2, there are plenty of exercises in this chapter which contain innumerable questions as well. All these questions are solved/answered by our in-house subject experts as mentioned earlier. Hence all of these are bound to be of superior quality and anyone can refer to these during the time of exam preparation. In order to score the best possible marks in the class, it is really important to understand all the concepts of the textbooks and solve the problems from the exercises given next to it.

Do not delay any more. Download the NCERT solutions for Class 8 Maths Chapter 14 Exercise 14.2 from Vedantu website now for better exam preparation. If you have the Vedantu app in your phone, you can download the same through the app as well. The best part of these solutions is these can be accessed both online and offline as well.

FAQs on NCERT Solutions for Class 8 Maths Chapter 14: Factorisation - Exercise 14.2

1. What is the Importance of NCERT Solutions for Class 8 Maths Chapter 14 Factorization?

Chapter 14 of Maths Class 8 deals in factorization. The definition of factorisation is explained in this PDF. The process of factorisation is the representation of a given statement as the product of two factors. These elements might be integers, variables, or algebraic expressions themselves. The PDF also states that it uses several systematic techniques to discover factors for the provided phrases. 

2. What are the Important Topics Covered in NCERT Solutions Class 8 Maths Chapter 14?

All key subjects of the factorization are covered in NCERT Solutions Class 8 Maths Chapter 14 including factors of natural numbers, factors of algebraic expressions, factorization techniques, and division of algebraic expressions. To access the PDFs of these NCERT Solutions for free you can refer to the official website of Vedantu or download the Vedantu app.

3. How many exercises are there in NCERT Solutions for Class 8 Maths Chapter 14?

There are 33 questions in Class 8 Maths Chapter 14 Factorization, most of which are short answer questions with subparts. Factoring algebraic equations and dividing polynomials by polynomials are the most common techniques used in these issues.

4. What is the meaning of factorisation?

Algebraic expression factorization is a crucial ability for advanced math courses. Factorization of expressions is a difficult procedure that necessitates a thorough grasp of factors and the methods for listing them. Students may swiftly gain this information by thoroughly practising NCERT Solutions Class 8 Maths Chapter 14 in order to prepare effectively for examinations. These solutions also help pupils build confidence in preparation for a variety of competitive studies.

5. What is the formula for factorisation?

The factorization formula breaks down a large number into smaller numbers or factors. A factor is a number that divides a given integer completely without leaving any residual. The factorization formula for a given value is as follows N = Xa × Yb × Zc

N = Any number 

X, Y, and Z = Factors of number N

a, b, and c = exponents of factors X, Y, and Z respectively.

6. What is factorisation algebra?

The term "algebraic factorization" refers to the process of identifying the factors of a given expression, which entails identifying two or more expressions whose product is the given expression. Factorization of algebraic expressions is the process of finding two or more expressions whose product is the given expression.