ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions

Mental Maths
Question 1.
Fill in the blanks:
(i) When an algebraic expression can be written as the product of two or more expressions then each of these expressions is called ……….. of the given expression.
(ii) The process of finding two or more expressions whose product is the given expression is called ………..
(iii) HCF of two or more monomials = (HCF of their ……….. coefficients) × (HCF of their literal coefficients)
(iv) HCB of literal coefficients = product of each common literal raised to the ……….. power.
(v) To factorise the trinomial of the form x2 + px + q, we need to find two integers a and b such that a + b = ……….. and ab = ………..
(vi) To factorise the trinomial of the form ax2 + bx + c, where a, b and c are integers, we split b into two parts such that ……….. of these parts is b and there is ……….. ac.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 1

Question 2.
State whether the following statements are true (T) or false (F):
(i) Factorisation is the reverse process of multiplication.
(ii) HCF of two or more polynomials (with integral coefficients) is the smallest common factor of the given polynomials.
(iii) HCF of 6x2y2 and 8xy3 is 2xy2.
(iv) Factorisation by grouping is possible only if the given polynomial contains an even number of terms.
(v) To factorise the trinomial of the form ax2 + bx + c where, a, b, c are integers we want to find two integers A and B such that
A + B = ac and AB = b
(vi) Factors of 4x2 – 12x + 9 are (2x – 3) (2x – 3).
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 2

Multiple Choice Questions
Choose the correct answer from the given four options (3 to 14):
Question 3.
H.C.F. of 6abc, 24ab2, 12a2b is
(a) 6ab
(b) 6ab2
(c) 6a2b
(d) 6abc
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 3

Question 4.
Factors of 12a2b + 15ab2 are
(a) 3a(4ab + 5b2)
(b) 3ab(4a + 5b)
(c) 3b(4a2 + 5ab)
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 4

Question 5.
Factors of 6xy – 4y + 6 – 9x are
(a) (3y – 2) (2x – 3)
(b) (3x – 2) (2y – 3)
(c) (2y – 3) (2 – 3x)
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 5

Question 6.
Factors of 49p3q – 36pq are
(a) p(7p + 6q) (7p – 6q)
(b) q(7p – 6) (7p + 6)
(c) pq(7p + 6) (7p – 6)
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 6

Question 7.
Factors of y(y – z) + 9(z – y) are
(a) (y – z) (y + 9)
(b) (z – y) (y + 9)
(c) (y – z) (y – 9)
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 7

Question 8.
Factors of (lm + l) + m + 1 are
(a) (lm + l )(m + l)
(b) (lm + m)(l + 1)
(c) l(m + 1)
(d) (l + 1)(m + 1)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 8

Question 9.
Factors of z2 – 4z – 12 are
(a) (z + 6)(z – 2)
(b) (z – 6)(z + 2)
(c) (z – 6)(z – 2)
(d) (z + 6)(z + 2)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 9

Question 10.
Factors of 63a2 – 112b2 are
(a) 63 (a – 2b)(a + 2b)
(b) 7(3a + 2b)(3a – 2b)
(c) 7(3a + 4b)(3a – 4b)
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 10

Question 11.
Factors of p4 – 81 are
(a) (p2 – 9)(p2 + 9)
(b) (p + 3)2 (p – 3)2
(c) (p + 3) (p – 3) (p2 + 9)
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 11

Question 12.
Factors of 3x + 7x – 6 are
(a) (3x – 2)(x + 3)
(b) (3x + 2) (x – 3)
(c) (3x – 2)(x – 3)
(d) (3x + 2) (x + 3)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 12

Question 13.
Factors of 16x2 + 40x + 25 are
(a) (4x + 5)(4x + 5)
(b) (4x + 5)(4x – 5)
(c) (4x + 5)(4x + 8)
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 13

Question 14.
Factors of x2 – 4xy + 4y2 are
(a) (x – 2y)(x + 2y)
(b) (x-2y)(x-2y)
(c) (x + 2y)(x + 2y)
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 14

Higher Order Thinking Skills (Hots)
Factorise the following
Question 1.
x2 + \(\left(a+\frac{1}{a}\right)\)x + 1
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 15

Question 2.
36a4 – 97a2b2 + 36b4
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 16

Question 3.
2x2 – \(\sqrt{3}\)x – 3
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 17

Question 4.
y(y2 – 2y) + 2(2y – y2) – 2 + y
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Objective Type Questions 18

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.5

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.5

Question 1.
Work out the following divisions:
(i) (35x + 28) ÷ (5x + 4)
(ii) 7p2q2(9r – 27) ÷ 63pq(r – 3)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.5 1

Question 2.
Divide as directed:
(i) 6(2x + 7) (5x – 3) ÷ 3(5x – 3)
(ii) 33pq (p + 3) (2q – 5) ÷ 11p (2q – 5)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.5 2

Question 3.
Factorise the expression and divide them as directed:
(i) (7x2 – 63x) ÷ 7(x – 3)
(ii) (3p2 + 17p + 10) ÷ (p + 5)
(iii) 10xy(14y2 + 43y – 21) ÷ 5x(7y – 3)
(iv) 12pqr(6p2 – 13pq + 6q2) ÷ 6pq(2p – 3q)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.5 4
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.5 4
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.5 5

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4

Factorise the following (1 to 11) polynomials:
Question 1.
(i) x2 + 3x + 2,
(ii) z2 + 10z + 24
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 1
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 2

Question 2.
(i) y2 – 7y + 12
(ii) m2 – 23m + 42
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 3

Question 3.
(i) y2 – 5y – 24,
(ii) t2 + 23t – 108
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 4

Question 4.
(i) 3x2 + 14x + 8,
(ii) 3y2 + 10y + 8
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 5

Question 5.
(i) 14x2 – 23x + 8,
(ii) 12x2 – x – 35
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 6

Question 6.
(i) 6x2 + 11x – 10
(ii) 5 – 4x – 12x2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 7

Question 7.
(i) 1 – 18y – 63y2,
(ii) 3x2 – 5xy – 12y2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 8

Question 8.
(i) x2 – 3xy – 40y2
(ii) 10p2q2 – 21pq + 9
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 9

Question 9.
(i) 2a2b2 + ab – 45
(ii) x (12x + 7) – 10
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 10

Question 10.
(i) (a + b)2 – 11(a + b) – 42
(ii) 8 + 6(p + q) – 5(p + q)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 11
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 12

Question 11.
(i) (x – 2y)2 – 6(x – 2y) + 5
(ii) 7 + 10(2x – 3y) – 8(2x – 3y)2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.4 13

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3

Question 1.
Factorise the following expressions using algebraic identities:
(i) x2 – 12x + 36
(ii) 36p2 – 60pq + 25q2
(iii) 9y2 + 66xy + 121y2
(iv) a4 + 6a2b2 + 9b4
(v) x2 + \(\frac{1}{x^{2}}\) + 2
(vi) x2 + x + \(\frac{1}{4}\)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 1
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 2
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 3

Factorise the following (2 to 13) expressions:
Question 2.
(i) 4p2 – 9
(ii) 4x2 – 169y2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 4

Question 3.
(i) 9x2y2 – 25
(ii) 16x2 – \(\frac{1}{144}\)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 5

Question 4.
(i) 20x2 – 45y2
(ii) \(\frac{9}{16}\) – 25a2b2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 6

Question 5.
(i) (2a + 3b)2 – 16c2
(ii) 1 – (b – c)2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 7

Question 6.
(i) 9 (x + y)2 – x2
(ii) (2m + 3n)2 – (3m + 2n)2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 8

Question 7.
(i) 25 (a + b)2 – 16 (a – b)2
(ii) 9 (3x + 2)2 – 4 (2x – 1)2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 9

Question 8.
(i) x3 – 25x
(ii) 63p2q2 – 7
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 10

Question 9.
(i) 32a2b – 72b3
(ii) 9 (a + b)3 – 25 (a + b)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 11

Question 10.
(i) x2 – y2 – 2y – 1
(ii) p2– 4pq + 4q2 – r2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 12

Question 11.
(i) 9x2 – y2 + 4y – 4
(ii) 4a2 – 4b2 + 4a + 1
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 13

Question 12.
(i) 625 – p4
(ii) 5y5 – 405y
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 14

Question 13.
(i) x4 – y4 + x2 – y2
(ii) 64a2 – 9b2 + 42bc – 49c2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.3 15

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2

Factorise the following (1 to 11) polynomials:
Question 1.
(i) x2 + xy – x – y
(ii) y2 – yz – 5y + 5z
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2 1

Question 2.
(i) 5xy + 7y – 5y2 – 7x
(ii) 5p2 – 8pq – 10p + 16q
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2 2

Question 3.
(i) a2b – ab2 + 3a – 3b
(ii) x3 – 3x2 + x – 3
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2 3

Question 4.
(i) 6xy2 – 3xy – 10y + 5
(ii) 3ax – 6ay – 8by + 4bx
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2 4

Question 5.
(i) x2 + xy (1 + y) + y3
(ii) y2 – xy (1 – x) – x3
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2 5

Question 6.
(i) ab2 + (a – 1) b – 1
(ii) 2a – 4b – xa + 2bx
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2 6

Question 7.
(i) 5ph – 10qk + 2rph – 4qrk
(ii) x2 – x(a + 2b) + 2a2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2 7

Question 8.
(i) ab (x2 + y2) – xy (a2 + b2)
(ii) (ax + by)2 + (bx – ay)2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2 8

Question 9.
(i) a3 + ab(1 – 2a) – 2b2
(ii) 3x2y – 3xy + 12x – 12
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2 9

Question 10.
(i) a2b + ab2 – abc – b2c + axy + bxy
(ii) ax2 – bx2 + ay2 – by2 + az2 – bz2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2 10

Question 11.
(i) x – 1 – (x – 1)2 + ax – a
(ii) ax + a2x + aby + by – (ax + by)2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.2 11

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.1

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.1

Factorise the following (1 to 8) polynomials:
Question 1.
(i) 8xy3 + 12x2y2
(ii) 15ax3 – 9ax2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.1 1

Question 2.
(i) 21 py2 – 56py
(ii) 4x3 – 6x2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.1 2

Question 3.
(i) 25abc2 – 15a2b2c
(ii) x2yz + xy2z + xyz2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.1 3

Question 4.
(i) 8x3 – 6x2 + 10x
(ii) 14mn + 22m – 62p
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.1 4

Question 5.
(i) 18p2q2 – 24pq2 + 30p2q
(ii) 27a3b3 – 18a2b3 + 75a3b2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.1 5

Question 6.
(i) 15a (2p – 3p) – 106 (2p – 3q)
(ii) 3a (x2 + y2) + 6b (x2 + y2)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.1 6

Question 7.
(i) 6(x + 2y)3 + 8(x + 2y)2
(ii) 14(a – 3b)3 – 21p(a – 3b)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.1 7

Question 8.
10a (2p + q)3 – 15b (2p + q)2 + 35(2p + q)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 11 Factorisation Ex 11.1 8

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress

Question 1.
Add the following expressions:
(i) -5x2y + 3xy2 – 7xy + 8, 12x2y – 5xy2 + 3xy – 2
(ii) 9xy + 3yz – 5zx, 4yz + 9zx – 5y, -5xz + 2x – 5xy
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 1

Question 2.
Subtract:
(i) 5a + 3b + 11c – 2 from 3a + 5b – 9c + 3
(ii) 10x2 – 8y2 + 5y – 3 from 8x2 – 5xy + 2y+ 5x – 3y
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 2

Question 3.
What must be added to 5x2 – 3x + 1 to get 3x3 – 7x2 + 8?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 3

Question 4.
Find the product of
(i) 3x2y and -4xy2
(ii) –\(\frac{4}{5}\)xy, \(\frac{5}{7}\)yz and –\(\frac{14}{9}\)zx
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 4

Question 5.
Multiply:
(i) (3pq – 4p2 + 5q2 + 7) by -7pq
(ii) (\(\frac{3}{4}\)x2y – \(\frac{4}{5}\)xy + \(\frac{5}{6}\)xy2) by – 15xyz
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 5

Question 6.
Multiply:
(i) (5x2 + 4x – 2) by (3 – x – 4x2)
(ii) (7x2 + 12xy – 9y2) by (3x2 – 5xy + 3y2)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 6

Question 7.
Simplify the following expressions and evaluate them as directed:
(i) (3ab – 2a2 + 5b2) x (2b2 – 5ab + 3a2) + 8a3b – 7b4 for a = 1, b = -1
(ii) (1.7x – 2.5y) (2y + 3x + 4) – 7.8x2 – 10y for x = 0, y = 1.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 7

Question 8.
Carry out the following divisions:
(i) 66pq2r3 ÷ 11qr2
(ii) (x3 + 2x2 + 3x) ÷ 2x
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 8

Question 9.
Divide 10x4 – 19x3 + 17x2 + 15x – 42 by 2x2 – 3x + 5.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 9

Question 10.
Using identities, find the following products:
(i) (3x + 4y) (3x + 4y)
(ii) \(\left(\frac{5}{2} a-b\right)\left(\frac{5}{2} a-b\right)\)
(iii) (3.5m – 1.5n) (3.5m + 1.5n)
(iv) (7xy – 2)(7xy + 7)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 10
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 11

Question 11.
Using suitable identities, evaluate the following:
(i) 1052
(ii) 972
(iii) 201 × 199
(iv) 872 – 132
(v) 105 × 107
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 12
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 13

Question 12.
Prove that following:
(i) (a + b)2 – (a – b)2 + 4ab
(ii) (2a + 3b)2 + (2a – 3b)2 = 8a2 + 18b2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 14

Question 13.
If x + \(\frac{1}{x}\) = 5, evaluate
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 15
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 16
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 17

Question 14.
If a + b = 5 and a2 + b2 = 13, find ab.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Check Your Progress 18

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions

Mental Maths
Question 1.
Fill in the blanks:
(i) A symbol which has a fixed value is called a ……….
(ii) A symbol which can be given various numerical values is called ……….. or ………
(iii) The various parts of an algebraic expression separated by + or – sign are called ………..
(iv) An algebraic expression having ………… terms is called a binomial.
(v) Each of the quantity (constant or literal) multiplied together to form a product is called a ………… of the product.
(vi) The terms having the same literal coefficients are called a ………… otherwise they are called …………
(vii) Degree of the polynomial is the greatest sum of the powers of ………… in each term.
(viii)An identity is equality which is true for ………… of variables in it.
(ix) (a + b)2 = …………
(x) (x + a) (x + b) = x2 + ………… + ab.
(xi) Dividend = ………… + remainder.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 1

Question 2.
State whether the following statements are true (T) or false (F):
(i) An algebraic expression having only one term is called a monomial.
(ii) A symbol which has fixed value is called a literal.
(iii) The term of an algebraic expression having no literal factor is called its constant term,
(iv) In any term of an algebraic expression the constant part is called literal coefficient of the term.
(v) An algebraic expression is called polynomial if the powers of the variables involved in it in each term are non-negative integers.
(vi) 5x2y2z, 3x2zy2, – \(\frac{4}{5}\) zx2y2 are unlike terms.
(vii) 5x + \(\frac{2}{x}\) + 7 is a polynomial of degree 1.
(viii) 3x2y + 7x + 8y + 9 is a polynomial of degree 3.
(ix) Numerical coefficient of -7x3y is 7.
(x) An equation is true for all values of variables in it.
(xi) (a – b)2 + 2ab = a2 + b2.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 2
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 3

Multiple Choice Questions
Choose the correct answer from the given four options (3 to 18):
Question 3.
The literal coefficient of -9xyz2 is
(a) -9
(b) xy
(c) xyz2
(d) -9xy
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 4

Question 4.
Which of the following algebraic expression is
(a) 3x2 – 2x + 7
(b) \(\frac{5 x^{3}}{2 x}\) + 3x2 + 8
(c) 3x + \(\frac{2}{x}\) + 7
(d) \(\sqrt{2}\)x2 + \(\sqrt{3}\)x + \(\sqrt{6}\)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 5

Question 5.
Which of the following algebraic expressions is not a monomial?
(a) 3x × y × z
(b) -5pq
(c) 8m2 × n ÷ 31
(d) 7x ÷ y – z
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 6

Question 6.
Degree of the polynomial 7x2yz2 + 6x3y2z2 – 5x + 8y is
(a) 4
(b) 5
(c) 6
(d) 7
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 7

Question 7.
a(b -c) + b(c – a) + c(a – b) is equal to
(a) ab + bc + ca
(b) 0
(c) 2(ab + bc + ca)
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 8

Question 8.
\(\frac{7}{5}\)xy – \(\frac{2}{3}\)xy + \(\frac{8}{9}\) xy is equal to
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 9
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 10

Question 9.
(3p2qr3) × (-4p3q2r2) x (7pq3r) is equal to
(a) 84p6q6r6
(b) -84p6q6r6
(c) 84p6q5r6
(d) -84p6q5r6
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 11

Question 10.
3m × (2m2 – 5mn + 4n2) is equal to
(a) 6m3 + 15m2n – 12mn2
(b) 6m3 – 15m2n + 12mn2
(c) 6m3 – 15m2n – 12mn2
(d) 6m3 + 15m2n + 12mn2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 12

Question 11.
Volume of a rectangular box whose adjacent edges are 3x2y, 4y2z and 5z2x respectively is
(a) 60xyz
(b) 60x2y2z2
(c) 60x3y3z3
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 13

Question 12.
(x – 1) (x + 2) is equal to
(a) 2x + 3
(b) x2 + 2x + 2
(c) x2 + 3x + 2
(d) x2 + 2x + 3
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 14

Question 13.
If x + \(\frac{1}{x}\) = 2, then x2 + \(\frac{1}{x^{2}}\) is equal to
(a) 4
(b) 2
(c) 0
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 15

Question 14.
If x2 + y2 = 9 and xy = 8, then x + y is equal to
(a) 25
(b) 5
(c) -5
(d) ±5
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 16

Question 15.
(102)2 – (98)2 is equal to
(a) 200
(b) 400
(c) 600
(d) 800
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 17

Question 16.
-50x3y2z2 divided by -5xyz is equal to
(a) 10xyz
(b) 10x2yz
(c) -10xyz
(d) -10x2yz
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 18

Question 17.
96 × 104 is equal to
(a) 9984
(b) 9974
(c) 9964
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 19

Question 18.
If the area of a rectangle is 24(x2yz + xy2z + xyz2) and its length is 8xyz, then its breadth is
(a) 3(x + y + z)
(b) 3xyz
(c) 3(x + y – z)
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 20

Higher Order Thinking Skills (Hots)
Question 1.
Using the identity (a + b) = a2 + 2ab + b2, derive the formula for (a + b + c)2. Hence, find the value of (2x – 3y + 4z)2.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 21

Question 2.
Using the product of algebraic expressions, find the formulas for (a + b)2 and (a – b).
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Objective Type Questions 22

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5

Question 1.
Using suitable identities, find the following products:
(i) (3x + 5) (3x + 5)
(ii) (9y – 5) (9y-5)
(iii) (4x + 11y) (4x – 11y)
(iv) \(\left(\frac{3}{2} m+\frac{2}{3} n\right)\left(\frac{3}{2} m-\frac{2}{3} n\right)\)
(v) \(\left(\frac{2}{a}+\frac{5}{b}\right)\left(\frac{2}{a}+\frac{5}{b}\right)\)
(vi) \(\left(\frac{p^{2}}{2}+\frac{2}{q^{2}}\right)\left(\frac{p^{2}}{2}-\frac{2}{q^{2}}\right)\)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 1
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 2
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 3

Question 2.
Using the identities, evaluate the following:
(i) 812
(ii) 972
(iii) 1052
(iv) 9972
(v) 6.12
(vi) 496 × 504
(vii) 20.5 × 19.5
(viii) 9.62
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 4
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 5
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 6

Question 3.
Find the following squares, using the identities:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 7
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 8
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 9

Question 4.
Using the identity, (x + a) (x + b) = x2 + (a + b)x + ab, find the following products:
(i) (x + 7) (x + 3)
(ii) (3x + 4) (3x – 5)
(iii) (p2 + 2q) (p2 – 3q)
(iv) (abc + 3) (abc – 5)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 10

Question 5.
Using the identity, (x + a) (x + b) = x2 + (a + b)x + ab, evaluate the following:
(i) 203 × 204
(ii) 8.2 × 8.7
(iii) 107 × 93
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 11

Question 6.
Using the identity a2 – b2 = (a + b) (a – b), find
(i) 532 – 472
(ii) (2.05)2 – (0.95)2
(iii) (14.3)2 – (5.7)2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 12

Question 7.
Simplify the following:
(i) (2x + 5y)2 + (2x – 5y)2
(ii) \(\left(\frac{7}{2} a-\frac{5}{2} b\right)^{2}-\left(\frac{5}{2} a-\frac{7}{2} b\right)^{2}\)
(iii) (p2 – q2r)2 + 2p2q2r
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 13
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 14

Question 8.
Show that:
(i) (4x + 7y)2 – (4x – 7y)2 = 112xy
(ii) \(\left(\frac{3}{7} p-\frac{7}{6} q\right)^{2}+p q=\frac{9}{49} p^{2}+\frac{49}{36} q^{2}\)
(iii) (p – q)(p + q) + (q – r)(q + r) + (r – p) (r + p) = 0
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 15
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 16

Question 9.
If x + \(\frac{1}{x}\) = 2, evaluate:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 17
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 18
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 19

Question 10.
If x = \(\frac{1}{x}\) = 7, ecaluate:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 20
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 21
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 22

Question 11.
If x2 + \(\frac{1}{x^{2}}\) = 23, evaluate:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 23
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 24
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 25

Question 12.
If a + b = 9 and = 10, find the value of a2 + b2.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 26

Question 13.
If a – b = 6 and a2 + b2 = 42, find the value of
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 27

Question 14.
If a2 + b2 = 41 and ab = 4, find the values of
(i) a + b
(ii) a – b
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.5 28

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4

Question 1.
Divide:
(i) – 39pq2r5 by – 24p3q3r
(ii) –\(\frac{3}{4}\)a2b3 by \(\frac{6}{7}\)a3b2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4 1
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4 2

Question 2.
Divide:
(i) 9x4 – 8x3 – 12x + 3 by 3x
(ii) 14p2q3 – 32p3q2 + 15pq2 – 22p + 18q by – 2p2q.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4 3

Question 3.
Divide:
(i) 6x2 + 13x + 5 by 2x + 1
(ii) 1 + y3 by 1 + y
(iii) 5 + x – 2x2 by x + 1
(iv) x3 – 6x2 + 12x – 8 by x – 2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4 4
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4 5
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4 6

Question 4.
Divide:
(i) 6x3 + x2 – 26x – 25 by 3x – 7
(ii) m3 – 6m2 + 7 by m – 1
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4 7
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4 8

Question 5.
Divide:
(i) a3 + 2a2 + 2a + 1 by + a2 + a + 1
(ii) 12x3 – 17x2 + 26x – 18 by 3x2 – 2x + 5
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4 9

Question 6.
If the area of a rectangle is 8x2 – 45y2 + 18xy and one of its sides is 4x + 15y, find the length of the adjacent side.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.4 10

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.3

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.3

Question 1.
Multiply:
(i) (5x – 2) by (3x + 4)
(ii) (ax + b) by (cx + d)
(iii) (4p – 7) by (2 – 3p)
(iv) (2x2 + 3) by (3x – 5)
(v) (1.5a – 2.5b) by (1.5a + 2.56)
(vi) \(\left(\frac{3}{7} p^{2}+4 q^{2}\right) \text { by } 7\left(p^{2}-\frac{3}{4} q^{2}\right)\)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.3 1
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.3 2
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.3 3

Question 2.
Multiply:
(i) (x – 2y + 3) by (x + 2y)
(ii) (3 – 5x + 2 × 2) by (4x – 5)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.3 4

Question 3.
Multiply:
(i) (3x2 – 2x – 1) by (2x2 + x – 5)
(ii) (2 – 3y – 5y2) by (2y – 1 + 3y2)
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.3 5

Question 4.
Simplify:
(i) (x2 + 3) (x – 3) + 9
(ii) (x + 3) (x – 3) (x + 4) (x – 4)
(iii) (x + 5) (x + 6) (x + 7)
(iv) (p + q – 2r) (2p – q + r) – 4qr
(v) (p + q) (r + s) + (p – q)(r – s) – 2(pr + qs)
(vi) (x + y + z) (x – y + z) + (x + y – z) (-x + y + z) – 4zx
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.3 6
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.3 7

Question 5.
If two adjacent sides of a rectangle are 5x2 + 25xy + 4y2 and 2x2 – 2xy + 3y2, find its area.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 10 Algebraic Expressions and Identities Ex 10.3 8

ML Aggarwal Class 8 Solutions for ICSE Maths