# NCERT Solutions for Class 8 Maths chapter-9 Algebraic Expressions and Identities

**NCERT solutions for class 8 maths** chapter 9 Algebraic Expressions and Identities is prepared by academic team of Physics Wallah. We have prepared solutions for all exercise with **importants questions** of chapter 9. Given below is step by step solutions of all questions given in NCERT textbook for chapter-9. Read chapter 9 theory make sure you have gone through the theory part of chapter-9 from NCERT textbook and you have learned the formula of the given chapter. Physics Wallah prepared a detail notes and additional questions for **class 8 maths** with short notes of all ** maths formula** of class 8 maths. do read these contents before moving to solve the exercise of NCERT chapter 9.

### NCERT Solutions for Class 8 Maths Exercise 9.1

**Question 1.**

Identify the terms, their coefficients for each of the following expressions:

(i)

(ii)** 1 + x + x²**

(iii)

(iv)**3 - pq + qr -rp**

(v) + - xy

(vi) **3 - pq + qr -rp**

**Solution :**

(i) Terms: and

Coefficient in is 5 and in is **-3**

(ii) Terms: **1, x **and** x²**

Coefficient of and coefficient of **x² ** is 1.

(iii) Terms: and ** z²**

Coefficient in is 4, coefficient of is -4 and coefficient of **z²** is 1.

(iv) Terms: **3, -pq, qr** and** -rp**

Coefficient of **-pq** is **-1,** coefficient of **qr** is 1 and coefficient of **-rp** is

(v) Terms: and** -xy**

Coefficient of is coefficient of is and coefficient of **-xy **is **-1.**

(vi) Terms: **0.3a, -0.6ab ** and **0.5b**

Coefficient of **0.3a** is 0.3, coefficient of **-0.6ab ** is **-0.6** and coefficient of **0.5b ** is 0.5.

**Question 2.**

Classify the following polynomials as monomials, binomials, trinomials. Which polynomials do not fit in any of these three categories:

**Solution :**

(i) Since contains two terms. Therefore it is binomial.

(ii) Since 1000 contains one terms. Therefore it is monomial.

(iii) Since contains four terms. Therefore it is a polynomial and it does not fit in above three categories.

(iv) Since contains three terms. Therefore it is trinomial.

(v) Since contains two terms. Therefore it is binomial.

(vi) Since contains three terms. Therefore it is trinomial.

(vii) Since contains three terms. Therefore it is trinomial.

(viii) Since contains two terms. Therefore it is binomial.

(ix) Since contains four terms. Therefore it is a polynomial and it does not fit in above three categories.

(x) Since** pqr** contains one terms. Therefore it is monomial.

(xi) Since contains two terms. Therefore it is binomial.

(xii) Since **2p + 2q** contains two terms. Therefore it is binomial.

**Question 3.**

Add the following:

(i)

(ii)

(iii)

(iv)

**Solution :**

(i)

Hence the sum if 0.

Hence the sum is ** ab + ac + bc.**

**Question 4.**

**Solution :**

### NCERT Solutions for Class 8 Maths Exercise 9.2

**Question 1.**

Find the product of the following pairs of monomials:

(i)

(ii)

(iii)

(iv)

(iv) **4p ,0**

**Solution :**

(i) = =

(ii) =

=

(iii) =

=

(iv) =

=

(v)= = 0

**Question 2.**

Find the areas of rectangles with the following pairs of monomials as their lengths and breadths respectively:

**Solution :**

(i) Area of rectangle

=

= sq. units

(ii) Area of rectangle

=

=

= **50mn** sq. units

(iii) Area of rectangle =

=

= sq. units

(iv) Area of rectangle =

=

= sq. units

(v) Area of rectangle =

=

= sq. units

**Question 3.**

Complete the table of products:

(i)

**Solution :**

(i)

**Question 4.**

Obtain the volume of rectangular boxes with the following length, breadth and height respectively:

(i)

(ii)

(iii)

(iv)

**Solution :**

(i) Volume of rectangular box

=

= cubic units

(ii) Volume of rectangular box

=

= cubic units

(iii) Volume of rectangular box

=

= cubic units

(iv) Volume of rectangular box

=

= cubic units

**Question 5.**

Obtain the product of:

(i)

(ii)

(iii)

(iv)

(v)

**Solution :**

(i)

=

(ii) =

=

(iii)

=

(iv)

=

(v)

=

### NCERT Solutions for Class 8 Maths Exercise 9.3

**Question 1.**

Carry out the multiplication of the expressions in each of the following pairs:

(i)

(ii)

(iii)

(iv)

(v)

**Solution :**

(i)

=

(ii)

=

(iii)

=

(iv)

=

(v) =

= 0 + 0 + 0 = 0

**Question 2.**

Complete the table:

**Solution :**

**Question 3.**

Find the product:

(i)

(ii)

(iii)

(iv)

**Solution :**

(i)

=

(ii)

=

=

(iii)

=

=

(iv) =

**Question 4.**

(a) Simplify: and find values for

(i)

(ii)

(b) Simplify: find its value for

(i)

(ii)

(iii)

**Solution :**

(a)

=

(i) For

=

= 108 – 45 + 3 = 66

(ii) For

=

=

=

(b)

=

(i) For a= 0,

=

= 0 + 0 + 0 + 5 = 5

(ii) For a = 1

=

= 1 + 1 + 1 + 5 = 8

(iii) For

=

= = =4

**Question 5.**

(a) Add: and

(b) Add:and

(c) Subtract: from

(d) Subtract: from

**Solution :**

(a)

=

=

(b) +

=

=

=

(c)

=

=

=

(d)

=

=

=

=

=

=

NCERT Solutions for Class 8 Maths Exercise 9.4

**Question 1.**

Multiply the binomials:

(i) and

(ii) and

(iii) and

(iv) and

(v) and

(vi) and

**Solution :**

(i)

=

=

=

(ii)

=

=

=

(iii)

=

=

=

(iv)

=

=

(v)

=

=

=

=

(vi)

=

=

=

**Question 2.**

Find the product:

(i)

(ii)

(iii)

(iv)

**Solution :**

(i)

=

= = 15 - x -2x²

(ii)

=

=

(iii)

=

=

(iv)

=

=

**Question 3.**

Simplify:

(i)

(ii)

(iii)

(iv)

(v)

(vi)

(vii)

(viii)

**Solution :**

(i)

=

=

=

(ii)

=

=

=

(iii)

=

=

(iv)

=

=

=

=** 4ac**

(v)

=

=

=

(vi)

=

=

(vii)

=

=

=

(viii)

=

=

=

### Notes,worksheet and solved question for Maths class 8

- class 8 maths notes on chapter Liner equation in one variable
- class 8 maths notes on chapter algebric expression
- class 8 maths notes on chapter Mensuration
- class 8 maths notes on chapter Square and square roots
- class 8 maths notes on chapter statistice
- class 8 maths notes on chapter practical Geometry
- class 8 maths notes on chapter commericial maths
- class 8 maths notes on chapter solid shape
- class 8 maths notes on chapter quadrilaterals
- class 8 maths notes on chapter exponents
- class 8 maths notes on chapter factorisation
- class 8 maths notes on chapter inverse proporation
- class 8 maths notes on chapter cube and cube roots

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