ML Aggarwal Solutions for Class 7 Maths Chapter 8- Algebraic Expressions

Class 7: Maths Chapter 8 solutions. Complete Class 7 Maths Chapter 8 Notes.

ML Aggarwal Solutions for Class 7 Maths Chapter 8- Algebraic Expressions

ML Aggarwal 7th Maths Chapter 8, Class 7 Maths Chapter 8 solutions

1. From the algebraic expressions using variables, constants, and arithmetic operations:
(i) 6 more than thrice a number x.

Solution:-

3x + 6

(ii) 5 times x is subtracted from 13.

Solution:-

13 – 5x

(iii) The numbers x and y both squared and added.

Solution:-

x² + y²

(iv) Number 7 is added to 3 times the product of p and q.

Solution:-

3pq + 7

(v) Three times of x is subtracted from the product of x with itself.

Solution:-

x² – 3x

(vi) Sum of the numbers m and n is subtracted from their product.

Solution:-

mn – (m + n)

2. A taxi charges ₹ 9 per km and a fixed charge of ₹ 50. If the taxi is hired for x km, write an algebraic expression for this situation.

Solution:-

From the question it is given that,

A taxi charges ₹ 9 per km

A fixed charge of ₹ 50

If the taxi is hired for x km = ₹ (9x + 50)

3. Write down the algebraic expression whose terms are:
(i) 5a, -3b, c

Solution:-

Expressions is defined as, numbers, symbols and operators (such as +. – , × and ÷) grouped together that show the value of something.

So, Expressions = 5a – 3b + c

(ii) x², -5x, 6

Solution:-

Expressions is defined as, numbers, symbols and operators (such as +. – , × and ÷) grouped together that show the value of something.

So, Expressions = x² – 5x + 6

(iii) x²y, xy, -xy²

Solution:-

Expressions is defined as, numbers, symbols and operators (such as +. – , × and ÷) grouped together that show the value of something.

So, Expressions = x²y + xy – xy²

4. Write all the terms of each of the following algebraic expressions:

(i) 3 – 7x

Solution:-

In algebra a term is either a single number or variable, or numbers and variables multiplied together. Terms are separated by + or – signs or sometimes by division.

Terms = 3, -7x

(ii) 2 – 5a + ½b

Solution:-

In algebra a term is either a single number or variable, or numbers and variables multiplied together. Terms are separated by + or – signs or sometimes by division.

Terms = 2, -5a, ½b

(iii) 3x⁵ + 4y³ – 7xy² + 3

Solution:-

In algebra a term is either a single number or variable, or numbers and variables multiplied together. Terms are separated by + or – signs or sometimes by division.

Terms = 3x⁵, 4y³, -7xy², 3

5. Identify the terms and their factors in the algebraic expressions given below:
(i) -4x + 5y
(ii) xy + 2x²y²
(iii) 1.2ab – 2.4b + 3.6a

Solution:-

Expressions is defined as, numbers, symbols and operators (such as +. – , × and ÷) grouped together that show the value of something.

In algebra a term is either a single number or variable, or numbers and variables multiplied together. Terms are separated by + or – signs or sometimes by division.

Factors is defined as, numbers we can multiply together to get another number.

Sl.No.	Expression	Terms	Factors
(i)	– 4x + 5y	-4x5y	-4, x5, y
(ii)	Xy + 2x2y2	xy2x2y2	x, y2, x, x, y, y
(iii)	1.2ab – 2.4b + 3.6a	1.2ab-2.4b3.6a	1.2, a, b-2.4, b3.6, a

6. Show the terms and their factors by tree diagrams of the following algebraic expressions:
(i) 8x + 3y²

Solution:-

Expression: 8x – 3y²

Terms: 8x, -3y²

Factors: 8, x; 3, y, y

(ii) y – y³

Solution:-

Expression: y – y³

Terms: y, -y³

Factors: y; -y, -y, -y

(iii) 5xy² + 7x²y

Solution:-

Expression: 5xy² + 7x²y

Terms: 5xy², 7x²y

Factors: 5, x, y, y; 7, x, x, y

(iv) -ab + 2b² – 3a²

Solution:-

Expression: -ab + 2b² – 3a²

Terms: -ab, 2b², -3a²

Factors: -a, b; 2, b, b; -3, a, a

7. Write down the numerical coefficient of each of the following:
(i) -7x
(ii) -2x³y²
(iii) 6abcd²

(iv) (2/3)pq²

Solution:-

A coefficient is a number used to multiply a variable (3x means 3 times x, so 3 is a coefficient) Variables on their own (without a number next to them) actually have a coefficient of 1 (x is really 1x)

Then,

(i) -7x numerical co-efficient is -7

(ii) -2x³y² numerical co-efficient is -2

(iii) 6abcd² numerical co-efficient is 6

(iv) (2/3)pq² numerical co-efficient is 2/3

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ML Aggarwal Solutions for Class 7 Maths Chapter 8- Algebraic Expressions

Download PDF: ML Aggarwal Solutions for Class 7 Maths Chapter 8- Algebraic Expressions PDF

Chapterwise ML Aggarwal Solutions for Class 7 Maths :

• Chapter 1- Integers
• Chapter 2- Fractions and Decimals
• Chapter 3- Rational Numbers
• Chapter 4- Exponents and Powers
• Chapter 5- Sets
• Chapter 6- Ratio and Proportion
• Chapter 7- Percentage and Its Applications
• Chapter 8- Algebraic Expressions
• Chapter 9- Linear Equations and Inequalitie
• Chapter 10- Lines and Angles
• Chapter 11- Triangles and its Properties
• Chapter 12- Congruence of Triangles
• Chapter 13- Practical Geometry
• Chapter 14- Symmetry
• Chapter 15- Visualising Solid Shapes
• Chapter 16- Perimeter and Area
• Chapter 17- Data Handling

About ML Aggarwal

M. L. Aggarwal, is an Indian mechanical engineer, educator. His achievements include research in solutions of industrial problems related to fatigue design. Recipient Best Paper award, Manipal Institute of Technology, 2004. Member of TSTE.