8th Standard CBSE Syllabus & Materials
8th Standard CBSE
CBSE 8th Social Science Theme D - Factors of Production - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme C - Universal Franchise and India's Electoral System - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme B - The Rise of the Marathas - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme B - Reshaping India's Political Map - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Social Science Theme A - Natural Resources and Their Use - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Science Keeping Time with Skies - New Model Questions Papers Study Material - QB365 Set A

Published on: 18/09/2019
Algebraic Expressions and Identities
Download CBSE Class 8th Standard CBSE Mathematics question papers, sample papers, important questions, and previous year solved papers in PDF format. Get free study materials, NCERT solutions, and exam preparation resources for Class 8th Standard CBSE Mathematics
Questions + Answers key
Take MCQ Mathematics Test

1.
Using identities, evaluate (99)2
2.
Using identities, evaluate (102)2
3.
Simplify (a + 7)(a2 + 3a + 5)
4.
Multiply (a2 + 2b2) and (5a - 3b)
5.
Multiply (-3x) and (-5y + 2)
6.
Find the product of 4xy, 5x2y2 and 633y3
7.
Find the product of 2x, Sy and 7z
8.
Find the areas of rectangles with the following pairs of monomials as their lengths and breadths respectively (3mn,4np)
9.
Find the areas of rectangles with the following pairs of monomials as their lengths and breadths respectively (4x,3x2)
10.
Find the areas of rectangles with the following pairs of monomials as their lengths and breadths respectively (20x2,5y2)
11.
Add the following:
ab - bc, bc - ca, ca - ab
12.
Identify the terms, their coefficients for each of the following expressions,
\(\frac { X }{ 2 } +\frac { Y }{ 2 } -XY\)
13.
Identify the terms, their coefficients for each of the following expressions,
3- pq+ qr- rp
14.
Subtract 13a -18ab+ 3b+16 from 22a+ 30ab+ 6b+ 8.
15.
Show on the number line z - 3.
1.
9801
2.
10404
3.
a3 + 10a2 + 26a + 35
4.
(a2 + 2b2) x (5a – 3b) = a2 (5a – 3b) + 2b2 x (5a – 3b)
= 5a3 – 3a2b + 10ab2 – 6b3
5.
15xy - 6x
6.
120 x6y6
7.
70 xyz
8.
We have,length = 3mn and breadth = 4np
∴Area of rectangle = Length x Breadth
=(3mn) x (4np) = (3 x 4)x(mn) x (np)
= 12 x m x (n x n)xp = 12mn2p
9.
We have,4x and breadth = 3x2
∴Area of rectangle = LengthxBreadth
= (4x) x (3x2) = (4 x 3)x(x x x2)
= 12 x (x3 ) = 12 x3
10.
We have,length = 20x2 and breadth = 5y2
∴ Area of rectangle = LengthxBreadth
= (20x2) x (5y2) = (20 x 5) x (x2 x y2) =100x2y2
11.
We have,ab - bc, bc - ca, ca - ab
On writing the given expressions in separate rows with like terms one below the other, we get
ab - bc
+bc - ca
-ab +ca
_____________
0 +0 +0
_____________
Thus, the sum of the expression is 0.
12.
We have\(\frac { X }{ 2 } +\frac { Y }{ 2 } -XY\)
| Terms | \(\frac { X }{ 2 } \) | \(\frac { Y }{ 2 } \) | -XY |
| Coefficients | \(\frac { 1 }{ 2 } \) | \(\frac { 1 }{ 2 } \) | -1 |
13.
We have, 3 - pq + qr - rp
| Terms | 3 | -pq | qr | -rp |
| Coefficients | 3 | -1 | 1 | -1 |
14.
22a + 30ab + 6b + 8
13a -18ab + 3b + 16
(-) (+) (-) (-)
__________________
9a + 48ab + 3b - 8
___________________
15.
We have, (z - 3)
For given expression (z - 3), the variable z has a position Z on the number line. Z may be anywhere on the number line but the value of(z - 3) is given by position P, 3 units to the left of Z.

8th Standard CBSE Syllabus & Materials
8th Standard CBSE
CBSE 8th Science Particulate Nature of Matter - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Science Pressure, Winds, Stroms and Cyclones - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Mathematics Quadrilaterals - New Model Questions Papers Study Material - QB365 Set A
NEW8th Standard CBSE
CBSE 8th Mathematics A story of Numbers - New Model Questions Papers Study Material - QB365 Set A
CBSE 8th Standard CBSE Subjects
CBSE Standards