Class 8 Algebraic Expressions And Identities CBSE Questions & Answers

Class 8 · Algebraic Expressions And Identities

This is Mathematics Class 8 Algebraic Expressions and Identities CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
Add: 7xy + 5yz – 3zx, 4yz + 9zx – 4y , –3xz + 5x – 2xy.
  • A
    5xy + 9yz +3zx + 4y
  • B
    5xy + 9yz +3zx + 5x
  • C
    None of these
  • D
    5xy + 9yz +3zx + 5x – 4y
    Correct
2
Subtract \({\text{5}}{x^{\text{2}}}--{\text{ 4}}{y^{\text{2}}}\) + 6y – 3 from \({\text{7}}{x^{\text{2}}}--{\text{ 4}}xy + {\text{ 8}}{y^{\text{2}}}\) + 5x – 3y.
  • A
    \({\text{2}}{x^{\text{2}}}--{\text{ 4}}xy + {\text{ 12}}{y^{\text{2}}}\)+ 5x – 9y
  • B
    None of these
  • C
    \({\text{2}}{x^{\text{2}}}--{\text{ 4}}xy + {\text{ 12}}{y^{\text{2}}}\)+ 5x – 9y + 3
    Correct
  • D
    \({\text{2}}{x^{\text{2}}}--{\text{ 4}}xy + {\text{ 12}}{y^{\text{2}}}\)+ 5x
3
Add ab – bc, bc – ca, ca – ab
  • A
    2ab
  • B
    0
    Correct
  • C
    2ac
  • D
    2bc
4
Add a – b + ab, b – c + bc, c – a + ac
  • A
    ab + bc
  • B
    ab + bc + ac
    Correct
  • C
    a + b + c
  • D
    None of these
5
5x × \({\text{4}}{x^{\text{2}}}\) = ?
  • A
    None of these
  • B
    \({\text{2}}0{{\text{x}}^{\text{2}}}\)
  • C
    20x
  • D
    \({\text{2}}0{{\text{x}}^{\text{3}}}\)
    Correct
6
5x × (– 4xyz) = ?
  • A
    \( - {\text{2}}0{{\text{x}}^{\text{2}}}{\text{z}}\)
  • B
    None of these
  • C
    \( - {\text{2}}0{{\text{x}}^{\text{2}}}{\text{yz}}\)
    Correct
  • D
    \( - {\text{2}}0{{\text{x}}^{\text{2}}}{\text{y}}\)
7
2x × 5y × 7z= ?
  • A
    70xz
  • B
    70xyz
    Correct
  • C
    70xy
  • D
    None of these
8
\({\text{4}}xy \times {\text{ 5}}{x^{\text{2}}}{y^{\text{2}}} \times {\text{ 6}}{x^{\text{3}}}{y^{\text{3}}} = \)?
  • A
    None of these
  • B
    \({\text{12}}0{{\text{x}}^{\text{6}}}{{\text{y}}^{\text{6}}}\)
    Correct
  • C
    \({\text{12}}0{{\text{x}}^{\text{5}}}{{\text{y}}^{\text{5}}}\)
  • D
    120xy
9
4x × 5y × 7z = ?
  • A
    140xz
  • B
    140xyz
    Correct
  • C
    140xy
  • D
    None of these
10
Obtain the product of xy, yz and zx
  • A
    \({{\text{x}}^{\text{2}}}{{\text{y}}^{\text{2}}}{{\text{z}}^{\text{2}}}\)
    Correct
  • B
    xyz
  • C
    None of these
  • D
    \({{\text{x}}^{\text{3}}}{{\text{y}}^{\text{3}}}{{\text{z}}^{\text{3}}}\)
11
Obtain the product of a, 2b, 3c, 6abc.
  • A
    None of these
  • B
    \({\text{36}}{{\text{a}}^{\text{2}}}{{\text{b}}^{\text{2}}}{{\text{c}}^{\text{2}}}\)
    Correct
  • C
    \({\text{6}}{{\text{a}}^{\text{2}}}{{\text{b}}^{\text{2}}}{{\text{c}}^{\text{2}}}\)
  • D
    36abc
12
(–3x) × (–5y + 2) = ?
  • A
    15xy
  • B
    6x
  • C
    15xy – 6x
    Correct
  • D
    None of these
13
5xy ×\(\left( {{y^{\text{2}}} + {\text{ 3}}} \right){\text{ }} = \)?
  • A
    None of these
  • B
    15xy
  • C
    \({\text{5}}x{y^{\text{2}}}\)+ 15xy
  • D
    \({\text{5}}x{y^{\text{3}}}\)+ 15xy
    Correct
14
(5y + 2) × 3x = ?
  • A
    15xy + 6x
    Correct
  • B
    6x
  • C
    None of these
  • D
    15xy
15
\({\text{3}}p \times {\text{ }}\left( {{\text{4}}{p^{\text{2}}} + {\text{ 5}}p + {\text{ 7}}} \right){\text{ }} = {\text{ }}?\)
  • A
    \({\text{12}}{p^{\text{3}}} + {\text{ 15}}{p^{\text{2}}} + {\text{ 21}}p\)
    Correct
  • B
    None of these
  • C
    \({\text{12}}{p^{\text{3}}} + {p^{\text{2}}} + {\text{ 21}}p\)
  • D
    \({\text{12}}{p^{\text{3}}} + {\text{ 15}}{p^{\text{2}}} + p\)