RD Sharma Solutions (Part -1) - Ex - 7.4, Algebraic Expressions, Class 7, Math Class 7 Notes | EduRev

RD Sharma Solutions for Class 7 Mathematics

Created by: Abhishek Kapoor

Class 7 : RD Sharma Solutions (Part -1) - Ex - 7.4, Algebraic Expressions, Class 7, Math Class 7 Notes | EduRev

The document RD Sharma Solutions (Part -1) - Ex - 7.4, Algebraic Expressions, Class 7, Math Class 7 Notes | EduRev is a part of the Class 7 Course RD Sharma Solutions for Class 7 Mathematics.
All you need of Class 7 at this link: Class 7

Question 1:

Simplify each of the following algebraic expressions by removing grouping symbols.
 2x + (5x − 3y)

Answer 1:

We have 
   2x + (5x − 3y)
Since the '+' sign precedes the parentheses, we have to retain the sign of each term in the parentheses when we remove them.
= 2x + 5x - 3y
= 7x - 3y


Question 2:

Simplify each of the following algebraic expressions by removing grouping symbols.
 3x − (y − 2x)

Answer 2:

We have
3x − (y − 2x)
Since the '-' sign precedes the parentheses, we have to change the sign of each term in the parentheses when we remove them. Therefore, we have
3x − y + 2x
= 5x - y


Question 3:

Simplify each of the following algebraic expressions by removing grouping symbols.
 5a − (3b − 2a + 4c)

Answer 3:

We have
5a − (3b − 2a + 4c)
Since the '-' sign precedes the parentheses, we have to change the sign of each term in the parentheses when we remove them.
= 5a - 3b + 2a - 4c
= 7a - 3b - 4c


Question 4:

Simplify each of the following algebraic expressions by removing grouping symbols.
 −2 (x2 − y2xy) − 3(x2y2 − xy)

Answer 4:

We have
− 2(x2 − y2 + xy) − 3(x2 + y2 − xy)
Since the '-' sign precedes the parentheses, we have to change the sign of each term in the parentheses when we remove them.
= - 2x2 + 2y2 - 2xy - 3x2 - 3y2 + 3xy
= - 2x2 - 3x2 + 2y2- 3y2 - 2xy + 3xy
= - 5x2 - y2 + xy


Question 5:

Simplify each of the following algebraic expressions by removing grouping symbols.
 3x + 2y − {x − (2y − 3)}

Answer 5:

We have
3x + 2y − {x − (2y − 3)}
First, we have to remove the small brackets (or parentheses): ( ). Then, we have to remove the curly brackets (or braces): { }.
Therefore,
= 3x + 2y − {x − 2y + 3}
= 3x + 2y − x + 2y - 3
= 2x + 4y - 3


Question 6:

Simplify each of the following algebraic expressions by removing grouping symbols.
 5a − {3a − (2 − a) + 4}

Answer 6:

We have
5a − {3a − (2 − a) + 4}
First, we have to remove the small brackets (or parentheses): ( ). Then, we have to remove the curly brackets (or braces): { }.
Therefore,
= 5a − {3a − 2 + a + 4}
= 5a − 3a + 2 - a - 4
= 5a - 4a - 2
= a - 2


Question 7:

Simplify each of the following algebraic expressions by removing grouping symbols.
a − [b − {a − (b − 1) + 3a}]

Answer 7:

First we have to remove the parentheses, or small brackets, ( ), then the curly brackets, { }, and then the square brackets [ ].
Therefore, we have
a - [b - {a - (b - 1) + 3a}]
= a - [b - {a - b + 1 + 3a}]
= a - [b - {4a - b + 1}]
= a - [b - 4a + b - 1]
= a - [2b - 4a - 1]
= a - 2b + 4a + 1
= 5a - 2b + 1


Question 8:

Simplify each of the following algebraic expressions by removing grouping symbols.
a − [2b − {3a − (2b − 3c)}]

Answer 8:

First we have to remove the small brackets, or parentheses, ( ), then the curly brackets, { }, and then the square brackets, [ ].
Therefore, we have
a - [2b - {3a - (2b - 3c)}]
= a - [2b - {3a - 2b + 3c}]
= a - [2b - 3a + 2b - 3c]
= a - [4b - 3a - 3c]
= a - 4b + 3a + 3c
= 4a - 4b + 3c

Complete Syllabus of Class 7

Dynamic Test

Content Category

Related Searches

MCQs

,

Free

,

Class 7

,

Math Class 7 Notes | EduRev

,

Summary

,

Algebraic Expressions

,

Algebraic Expressions

,

Class 7

,

pdf

,

Previous Year Questions with Solutions

,

video lectures

,

Viva Questions

,

Exam

,

Algebraic Expressions

,

mock tests for examination

,

Math Class 7 Notes | EduRev

,

RD Sharma Solutions (Part -1) - Ex - 7.4

,

Math Class 7 Notes | EduRev

,

Sample Paper

,

RD Sharma Solutions (Part -1) - Ex - 7.4

,

Important questions

,

Class 7

,

Objective type Questions

,

shortcuts and tricks

,

past year papers

,

practice quizzes

,

RD Sharma Solutions (Part -1) - Ex - 7.4

,

Extra Questions

,

study material

,

ppt

,

Semester Notes

;