S.chand publication New Learning Composite mathematics solution of class 8 Chapter 5 Algebraic Expressions Exercise 5B

 Exercise 5B


Q1 | Ex-5B | Class 8 | Algebraic Expressions | S.Chand | New Learning Composite | myhelper


Question 1

Find the product of the following pairs of monomials.

(a) 5, 2x

Sol :

=5×2x=10


(b) -3y, 4y

Sol :

=-12y2


(c) -6p, -8pqr

Sol :

=-6p×8pqr=48p2qr


(d) 12p5, -5p

Sol :

=12p5×-5p=-60p6




Q2 | Ex-5B | Class 8 | Algebraic Expressions | S.Chand | New Learning Composite | myhelper

Question 2

Find the area of a rectangle whose length is 6x3y2 units and breadth is 3xy2 units.

Sol :
Length of rectangle=6x3y2

Breadth of rectangle=3xy2

∴Area of rectangle=Length×Breadth
=6x3y2×3xy2
=18x4y4



Q3 | Ex-5B | Class 8 | Algebraic Expressions | S.Chand | New Learning Composite | myhelper

Question 3

Simplify:

(a) (3y3 ) (-3y2)

Sol : -9y5


(b) (-8x5) (2x)

Sol : -16x6


(c) (-4m2n) (-3mn2)

Sol : +12m3n3


(d) (x4) (x3) (x)

Sol : x8


(e) (-4a) (5ab) (3b)

Sol : -60a2b2


(f) (-x3y2) (xy) (2y)

Sol : -2x4y4


(g) (-1/3 a3) (9a) (-2a4)

Sol : 6a8


(h) (-q)3 (2q)2

Sol : -4q5


(i) (2x)2 (3x)3

Sol : 108x5


(j) (-4z) (-5z2)3

Sol : 500z7


(k) (-3y)2 (-3y)3

Sol : -243y5


(l) (-0.5a2b) (-2ab)3

Sol : 4a5b4




Q4 | Ex-5B | Class 8 | Algebraic Expressions | S.Chand | New Learning Composite | myhelper

Question 4

Find a monomial equivalent to the given expression.

(a) ( 4a3b2) (3a3b4) + (2ab)6

Sol :

=12a6b6+64a6b6

=76a6b6


(b) (4x3) (2x)4 – (7x)2 (3x5)

Sol :

=64x7-147x7

=-83x7


(c) (5p2) (-2q) (3q) + (7p2) (2q2) + (-3p) (-5p) (4q2)

Sol :

=-30p2q2+14p2q2+60p2q2

=44p2q2


(d) (- 3xyz) (4x2yz) – (5y2) (2xz2) (-x2)

Sol :

=-12x3y2z2+10x3y2z2

=-2x3y2z2

No comments:

Post a Comment

Contact Form

Name

Email *

Message *