Punjab State Board PSEB 8th Class Maths Book Solutions Chapter 14 Factorization Ex 14.3 Textbook Exercise Questions and Answers.
PSEB Solutions for Class 8 Maths Chapter 14 Factorization Ex 14.3
1. Carry out the following divisions:
Question (i)
28x4 ÷ 56x
Solution:
Question (ii)
– 36y3 ÷ 9y2
Solution:
Question (iii)
66pq2r3 ÷ 11qr2
Solution:
Question (iv)
34x3y3z3 ÷ 51 xy2z3
Solution:
Question (v)
12a8b8 ÷ (- 6a6b4)
Solution:
2. Divide the given polynomial by the given monomial:
Question (i)
(5x2 – 6x) ÷ 3x
Solution:
Question (ii)
(3y8 – 4y6 + 5y4) ÷ y4
Solution:
Question (iii)
8 (x3y2z2 + x2y3z2 ÷ 4 x2y2z2)
Solution:
Question (iv)
(x3 + 2x2 + 3x) ÷ 2x
Solution:
Question (v)
(P3 q6 – p6 q3) ÷ p3 q3
Solution:
3. Work out the following divisions:
Question (i)
(10x – 25) ÷ 5
Solution:
= \(\frac{10 x-25}{5}\)
= \(\frac{5(2 x-5)}{5}\)
= 2x – 5
Question (ii)
(10x-25) ÷ (2x – 5)
Solution:
= \(\frac{10 x-25}{2 x-5}\)
= \(\frac{5(2 x-5)}{(2 x-5)}\)
= 5
Question (iii)
10y (6y + 21) ÷ 5 (2y + 7)
Solution:
= \(\frac{10 y(6 y+21)}{5(2 y+7)}\)
= \(\frac{2 \times 5 \times y \times 3 \times(2 y+7)}{5(2 y+7)}\)
= 2 × y × 3
= 6y
Question (iv)
9x2y2(3z – 24) ÷ 27xy (z – 8)
Solution:
Question (v)
96 abc (3a – 12) (5b – 30) ÷ 144 (a – 4)(b – 6)
Solution:
= \(\frac{96 a b c(3 a-12)(5 b-30)}{144(a-4)(b-6)}\)
= \(\frac{2 \times 2 \times 2 \times 2 \times 2 \times 3 \times a \times b \times c \times 3 \times(a-4) \times 5 \times(b-6)}{2 \times 2 \times 2 \times 2 \times 3 \times 3 \times(a-4) \times(b-6)}\)
= 2 × 5 × a × b × c
= 10 abc
4. Divide as directed:
Question (i)
5 (2x + 1) (3x + 5) ÷ (2x + 1)
Solution:
= \(\frac{5(2 x+1)(3 x+5)}{(2 x+1)}\)
= \(\frac{5 \times(3 x+5)}{1}\)
= 5(3x + 5)
Question (ii)
26xy (x + 5) (y – 4) ÷ 13x (y – 4)
Solution:
= \(\frac{26 x y(x+5)(y-4)}{13 x(y-4)}\)
= \(\frac{2 \times 13 \times x \times y(x+5)(y-4)}{13 x(y-4)}\)
= 2y(x + 5)
Question (iii)
52pqr (p + q) (q + r) (r + p) ÷ 104pq (q + r) (r + p)
Solution:
= \(\frac{52 p q r(p+q)(q+r)(r+p)}{104 p q(q+r)(r+p)}\)
= \(\frac{52 \times p \times q \times r \times(p+q)(q+r)(r+p)}{2 \times 52 \times p \times q \times(q+r)(r+p)}\)
= \(\frac{r \times(p+q)}{2}\)
= \(\frac {1}{2}\)r (p + q)
Question (iv)
20 (y + 4) (y2 + 5y + 3) ÷ 5 (y + 4)
Solution:
= \(\frac{20(y+4)\left(y^{2}+5 y+3\right)}{5(y+4)}\)
= \(\frac{2 \times 2 \times 5 \times(y+4)\left(y^{2}+5 y+3\right)}{5(y+4)}\)
= 2 × 2 × (y2 + 5y + 3)
= 4(y2 + 5y + 3)
Question (v)
x (x + 1) (x + 2) (x + 3) ÷ x (x + 1)
Solution:
= \(\frac{x(x+1)(x+2)(x+3)}{x(x+1)}\)
= \(\frac{(x+2)(x+3)}{1}\)
= (x + 2)(x + 3)
5. Factorise the expressions and divide them as directed:
Question (i)
(y2 + 7y + 10) ÷ (y + 5)
Solution:
First we factorise
y2 + 7y + 10
= y2 + 5y + 2y + 10
= y (y + 5) + 2 (y + 5)
= (y + 5) (y + 2)
∴ (y2 + 7y + 10) ÷ (y + 5)
= \(\frac{(y+5)(y+2)}{(y+5)}\)
= y + 2
Question (ii)
(m2 – 14m – 32) ÷ (m + 2)
Solution:
First we factorise
m2 – 14m – 32
= m2 – 16m + 2m – 32
= m (m – 16) + 2 (m – 16)
= (m – 16) (m + 2)
∴ (m2 – 14m – 32) ÷ (m + 2)
= \(\frac{(m-16)(m+2)}{m+2}\)
= m – 16
Question (iii)
(5p2 – 25p + 20) ÷ (p – 1)
Solution:
First we factorise
5p2 – 25p + 20
= 5 (p2 – 5p + 4)
= 5 (p2 – 4p – p + 4)
= 5 [p (p – 4) – 1 (p – 4)]
= 5 (p – 4) (p – 1)
∴ (5p2 – 25p + 20) ÷ (p – 1)
= \(\frac{5(p-4)(p-1)}{p-1}\)
= 5 (p – 4)
Question (iv)
4yz (z2 + 6z – 16) ÷ 2y (z + 8)
Solution:
= \(\frac{4 y z\left(z^{2}+6 z-16\right)}{2 y(z+8)}\)
= \(\frac{2 z\left(z^{2}+6 z-16\right)}{z+8}\)
Now, factorise
z2 + 6z – 16
= z2 + 8z – 2z – 16
= z (z + 8) – 2 (z + 8)
= (z + 8) (z – 2)
∴ 4yz (z2 + 6z – 16) ÷ 2y (z + 8)
= \(\frac{2 z(z+8)(z-2)}{z+8}\)
= 2z (z – 2)
Question (v)
5pq (p2 – q2) ÷ 2p(p + q)
Solution:
Question (vi)
12xy (9x2 – 16y2) ÷ 4xy (3x + 4y)
Solution:
= \(\frac{12 x y\left(9 x^{2}-16 y^{2}\right)}{4 x y(3 x+4 y)}\)
= \(\frac{12 x y(3 x-4 y)(3 x+4 y)}{4 x y(3 x+4 y)}\)
= 3 (3x – 4y)
Question (vii)
39y3 (50y2 – 98) ÷ 26y2 (5y + 7)
Solution: