Selina Concise Mathematics Class 9 ICSE Solutions Chapter 5 - Factorisation

Selina Concise Mathematics Class 9 ICSE Solutions Factorisation

Selina ICSE Solutions for Class 9 Maths Chapter 5  Factorisation

Exercise 5(A)

1.

Solution 1:

2.

Solution 2:

3.

Solution 3:

4.Factorise by taking out the common factors:

2 (2x - 5y) (3x + 4y) - 6 (2x - 5y) (x - y)

Solution 4:

5.Factorize by the grouping method:

a³ + a - 3a² - 3

Solution 5:

6.Factorize by the grouping method:

16 (a + b)² - 4a - 4b

Solution 6:

7.Factorize by the grouping method:

a⁴ - 2a³ - 4a + 8

Solution 7:

8.Factorize by the grouping method:

ab - 2b + a² - 2a

Solution 8:

9.Factorize by the grouping method:

ab (x² + 1) + x (a² + b²)

Solution 9:

10.Factorize by the grouping method:
a² + b - ab - a

Solution 10:

11.Factorize by the grouping method:
(ax + by)² + (bx - ay)²

Solution 11:

12.Factorize by the grouping method:
a²x² + (ax² + 1) x + a

Solution 12:

13.Factorize by the grouping method:
(2a-b)² -10a + 5b

Solution 13:

14.Factorize by the grouping method:

a (a -4) - a + 4

Solution 14:

15.Factorize by the grouping method:

y² - (a + b) y + ab

Solution 15:

16.Factorize by the grouping method:

Solution 16:

17.Factorize by the grouping method:
x² + y² + x + y + 2xy

Solution 17:

18.Factorize by the grouping method:
a² + 4b² - 3a + 6b - 4ab

Solution 18:

19.Factorize by the grouping method:

m (x - 3y)² + n (3y - x) + 5x - 15y

Solution 19:

20.Factorize by the grouping method:
x (6x - 5y) - 4 (6x - 5y)²

Solution 20:

Exercise 5(B)

1.Factorize:
a² + 10a + 24

Solution 1:

2.Factorize:
a² - 3a - 40

Solution 2:

3.Factorize:
1 - 2a - 3a²

Solution 3:

4.Factorize:
x² - 3ax - 88a²

Solution 4:

5.Factorize:
6a² - a-15

Solution 5:

6.Factorize:
24a³ + 37a² - 5a

Solution 6:

7.Factorize:

a(3a - 2) - 1

Solution 7:

8.Factorize:
a²b² + 8ab - 9

Solution 8:

9.Factorize:

3 - a (4 + 7a)

Solution 9:

10.Factorize:

(2a + b)² - 6a - 3b - 4

Solution 10:

11.Factorize:

1 - 2 (a+ b) - 3 (a + b)²

Solution 11:

12.Factorize:

3a² - 1 - 2a

Solution 12:

.

13.Factorize:

x² + 3x + 2 + ax + 2a

Solution 13:

14.Factorize:

(3x - 2y)² + 3 (3x - 2y) - 10

Solution 14:

15.Factorize:

5 - (3a² - 2a) (6 - 3a² + 2a)

Solution 15:

16.Find each trinomial (quadratic expression), given below, find whether it is factorisable or not. Factorise, if possible.

(i) x² - 3x - 54

(ii) 2x² - 7x - 15

(iii) 2x² + 2x - 75

(iv) 3x² + 4x - 10

(v) x(2x - 1) - 1 

Solution 16:

Exercise 5(C)


1.Factorize :
25a² - 9b²

Solution 1:

2.Factorize :
a² - (2a + 3b)²

Solution 2:

3.Factorize :
a² - 81 (b-c)²

Solution 3:

4.Factorize :
25(2a - b)² - 81b²

Solution 4:

5.Factorize :
50a³ - 2a

Solution 5:

6.Factorize :
4a²b - 9b³

Solution 6:

7.Factorize :
3a⁵ - 108a³

Solution 7:

8.Factorize :
9(a - 2)² - 16(a + 2)²

Solution 8:

9.Factorize :
a⁴ - 1

Solution 9:

10.Factorize :
a³ + 2a² - a-2

Solution 10:

11.Factorize :
(a + b)³ - a - b

Solution 11:

12.Factorize :

a (a - 1) - b (b - 1)

Solution 12:

13.Factorize :
4a² - (4b² + 4bc + c²)

Solution 13:

14.Factorize :
4a² - 49b² + 2a - 7b

Solution 14:

15.Factorize :
9a² + 3a - 8b - 64b²

Solution 15:

16.Factorize :
4a² - 12a + 9 - 49b²

Solution 16:

17.Factorize :
4xy - x² - 4y² + z²

Solution 17:

18.Factorize :
a² + b² - c² - d² + 2ab - 2cd

Solution 18:

19.Factorize :
4x² - 12ax - y² - z² - 2yz + 9a²

Solution 19:

20.Factorize :
(a² - 1) (b² - 1) + 4ab

Solution 20:

21.Factorize :
x⁴ + x² + 1

Solution 21:

22.Factorize :
(a² + b² - 4c²)² - 4a²b²

Solution 22:

23.Factorize :
(x² + 4y² - 9z²)² - 16x²y²

Solution 23:

24.(a + b) ² - a² + b²

Solution 24:

25.a² - b² - (a + b) ²

Solution 25:

26.9a² - (a² - 4) ²

Solution 26:

27.

Solution 27:

28.

Solution 28:

29.4x⁴ - x² - 12x - 36

Solution 29:

30.a² ( b + c) - (b + c)³

Solution 30:

Exercise 5(D)

1.Factorize :
a³ - 27

Solution 1:

2.Factorize :
1 - 8a³

Solution 2:

3.Factorize :
64 - a³b³

Solution 3:

4.Factorize :
a⁶ + 27b³

Solution 4:

5.Factorize :
3x⁷y - 81x⁴y⁴

Solution 5:

6.Factorize :
a³ - 

Solution 6:

7.Factorize :
a³ + 0.064

Solution 7:

8.Factorize :
a⁴ - 343a

Solution 8:

9.Factorize :
(x - y)³ - 8x³

Solution 9:

10.Factorize :

Solution 10:

11.Factorize :
a⁶ - b⁶

Solution 11:

12.Factorize :
a⁶ - 7a³ - 8

Solution 12:

13.Factorize :
a³ - 27b³ + 2a²b - 6ab²

Solution 13:

14.Factorize :
8a³ - b³ - 4ax + 2bx

Solution 14:

15.Factorize :
a - b - a³ + b³

Solution 15:

16.Factorize :
2x³ + 54y³ - 4x - 12y

Solution 16:

17.Show that:

(i) 13³ - 5³ is divisible by 8

(ii)35³ + 27³ is divisible by 62

Solution 17:

Exercise 5(E)

1.Factorize :

Solution 1:

2.Factorize :

Solution 2:

3.Factorize :

Solution 3:

4.Factorize :

Solution 4:

5.Factorize :
4x⁴ + 9y⁴ + 11x²y²

Solution 5:

6.Factorize :

Solution 6:

7.Factorize :
a - b - 4a² + 4b²

Solution 7:

8.Factorize :
(2a - 3)² - 2 (2a - 3) (a - 1) + (a - 1)²

Solution 8:

9.Factorize :
(a² - 3a) (a² + 3a + 7) + 10

Solution 9:

10.Factorize :
(a² - a) (4a² - 4a - 5) - 6

Solution 10:

11.Factorize :
x⁴ + y⁴ - 3x²y²

Solution 11:

12.Factorize :
5a² - b² - 4ab + 7a - 7b

Solution 12:

13.Factorize :
12(3x - 2y)² - 3x + 2y - 1

Solution 13:

14.Factorize :
4(2x - 3y)² - 8x+12y - 3

Solution 14:

15.Factorize :
3 - 5x + 5y - 12(x - y)²

Solution 15:

16.9x ² + 3x - 8y - 64y²

Solution 16:

17.

Solution 17:

18.

Solution 18:

19.2(ab + cd) - a² - b² + c² + d²

Solution 19:

20.

Solution 20:

Selina Concise Mathematics Class 9 ICSE Solutions Chapter 5 - Factorisation