Everything
Class 6

Class 6 Maths (Ganita Prakash)

Class 6 Science (Curiosity)

Class 6 Social Science

Class 6 English
Class 7

Class 7 Maths (Ganita Prakash - Part 1 and Part 2)

Class 7 Science (Curiosity)

Class 7 Social Science

Class 7 English
Class 8

Class 8 Maths (Ganita Prakash - Part 1 & Part 2)

Class 8 Science (Curiosity)

Class 8 Social Science

Class 8 English
Class 9

Class 9 Maths (Ganita Manjari - Part 1)

Class 9 Science (Exploration)

Class 9 Social Science

Class 9 English
Class 10

Class 10 Maths

Class 10 Science

Class 10 Social Science

Class 10 English
Class 11

Class 11 Maths

Class 11 Accountancy

Class 11 English

Class 11 Computer Science (Python)
Class 12

Class 12 Maths

Class 12 English

Class 12 Economics

Class 12 Accountancy

Class 12 Physics

Class 12 Chemistry

Class 12 Biology

Class 12 Computer Science (Python)

Class 12 Physical Education
Courses

GST and Accounting Course

Excel Course

Tally Course

Finance and CMA Data Course

Payroll Course
Interesting

Learn English

Learn Excel

Learn Tally

Learn GST (Goods and Services Tax)

Learn Accounting and Finance
Popular

GST Demo

GST Tax Invoice Format

Accounts Tax Practical

Tally Ledger List
Classes
- Class 6
- Class 7
- Class 8
- Class 9
- Class 10
- Class 11
- Class 12
Maths
Science
Finance

Class 12
Class 11
Class 10
Class 9
Class 8
Class 7
Class 6
Practice
GST
Accounts Tax
Englishtan
Excel

Class 6 Maths (Ganita Prakash)
Class 6 Maths (old NCERT)
Class 6 Science (Curiosity)
Class 6 Science (old NCERT)
Class 6 Social Science
Class 6 English

Class 7 Maths (Ganita Prakash)
Class 7 Maths (Ganita Prakash - Part 2)
Class 7 Maths (old NCERT)
Class 7 Science (Curiosity)
Class 7 Science (old NCERT)
Class 7 Social Science
Class 7 English

Class 8 Maths (Ganita Prakash)
Class 8 Maths (Ganita Prakash - Part 2)
Class 8 Maths (old NCERT)
Class 8 Science (Curiosity)
Class 8 Science (old NCERT)
Class 8 Social Science
Class 8 English

Class 9 Maths (Ganita Manjari - Part 1)
Class 9 Maths (old NCERT)
Class 9 Science (Exploration)
Class 9 Science (old NCERT)
Class 9 Social Science
Class 9 English

Class 10 Maths
Class 10 Science
Class 10 Social Science
Class 10 English

Class 11 Maths
Class 11 Accountancy
Class 11 Computer Science (Python)
Class 11 English

Class 12 Maths
Class 12 English
Class 12 Economics
Class 12 Accountancy
Class 12 Physics
Class 12 Chemistry
Class 12 Biology
Class 12 Computer Science (Python)
Class 12 Physical Education

GST and Accounting Course
Excel Course
Tally Course
Finance and CMA Data Course
Payroll Course

Learn English
Learn Excel
Learn Tally
Learn GST (Goods and Services Tax)
Learn Accounting and Finance

GST Demo
GST Tax Invoice Format
Accounts Tax Practical
Tally Ledger List

Chapter 1 Class 9 Number Systems
Serial order wise
Examples

Examples pages

Example 1 (i) Example 1 (ii) Example 1 (iii) Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Example 13 Example 14 Example 15 (i) Example 15 (ii) Example 15 (iii) Example 15 (iv) Example 16 Example 17 Example 18 Example 19 Example 20 (i) Example 20 (ii) Example 20 (iii) Example 20 (iv) Question 1 Next category Visualise Decimal Numbers on the number line →

Examples

Example 1 (i)

Example 1 (ii)

Example 1 (iii) Important

Example 2

Example 3

Example 4 Important

Example 5

Example 6

Example 7 Important

Example 8

Example 9 Important

Example 10 Important

Example 11 Important

Example 12

Example 13

Example 14 Important

Example 15 (i) Important

Example 15 (ii)

You are here

Example 15 (iii)

Example 15 (iv)

Example 16

Example 17

Example 18

Example 19 Important

Example 20 (i)

Example 20 (ii)

Example 20 (iii) Important

Example 20 (iv) Important

Question 1

Visualise Decimal Numbers on the number line →

Chapter 1 Class 9 Number Systems

Serial order wise

Ex 1.1
Ex 1.2
Ex 1.3
Ex 1.4
Ex 1.5
Examples
Visualise Decimal Numbers on the number line

Example 15 (ii) - Chapter 1 Class 9 Number Systems

Last updated at August 14, 2026 by Teachoo

Example 15 (ii) - Simplify (5 + √5) (5 - √5) - Teachoo [with Video] - Examples

Next: Example 15 (iii) → Remove Ads

Examples pages

Teachoo · Class 9 Class 9, made simpler Clear concepts, step by step Practice important questions Keep learning with Teachoo Explore Class 9 →

Transcript

Example 16 Simplify the following expressions: (ii) (5 + 5) (5 - 5) (5 + 5) (5 - 5) We know that, (a + b) (a-b) = a2 b2 Putting a = 5, b = 5 = 52 ( 5)2 = 25 5 = 20

Chapter 1 Class 9 Number Systems
Serial order wise

Examples

Example 1 (i)

Example 1 (ii)

Example 1 (iii) Important

Example 2

Example 3

Example 4 Important

Example 5

Example 6

Example 7 Important

Example 8

Example 9 Important

Example 10 Important

Example 11 Important

Example 12

Example 13

Example 14 Important

Example 15 (i) Important

Example 15 (ii)

You are here

Example 15 (iii)

Example 15 (iv)

Example 16

Example 17

Example 18

Example 19 Important

Example 20 (i)

Example 20 (ii)

Example 20 (iii) Important

Example 20 (iv) Important

Question 1

Visualise Decimal Numbers on the number line →

Made by

Davneet Singh

Davneet Singh is an IIT Kanpur graduate and has been teaching for 16+ years. At Teachoo, he breaks down Maths, Science and Computer Science into simple steps so students understand concepts deeply and score with confidence.

Many students prefer Teachoo Black for a smooth, ad-free learning experience.

Go ad-free with Teachoo Black

Adblock detected

Skip every ad. Keep every answer.

Teachoo Black gives you a clean, uninterrupted study experience on every page.

Go ad-free →

A second ad-free Teachoo reminder

One last thing

This is what ad-free feels like.

No banners. No interruptions. Just the lesson.

Go ad-free →

Please login to view more pages. It's free :)

Teachoo gives you a better experience when you're logged in. Please login :)

Teachoo is the best place to learn Maths, Science, GST and Finance (using AI)

Download Our Apps

Android App
iOS App

Classes

Class 6 - NCERTSolutions, Worksheets, MCQ
Class 7 - NCERT Solutions, Worksheets, MCQ
Class 8 - NCERT Solutions, Worksheets, MCQ
Class 9 - NCERT Solutions, Worksheets, MCQ
Class 10 - NCERT Solutions, Worksheets, MCQ
Class 11 - NCERT Solutions, Worksheets, MCQ
Class 12 - NCERT Solutions, Worksheets, MCQ

Useful Resources

GST, Income Tax and Tally Course
Teachoo Ad free version
Worksheets and Quizzes
Skillistan
GST Simulation Portal

Sample Paper Solutions

Class 10 Maths
Class 10 Science
Class 10 English
Class 10 Social Science
Class 12 Maths
Class 12 English

Maths - Useful links

Class 6 Maths NCERT Solutions (Ganita Prakash)
Class 7 Maths NCERT Solutions (Ganita Prakash - Part 1 and 2)
Class 8 Maths NCERT Solutions (Ganita Prakash - Part 1 and 2)
Class 9 Maths NCERT Solutions (Ganita Manjari - Part 1)
Class 10 Maths NCERT Solutions
Class 11 Maths NCERT Solutions
Class 12 Maths NCERT Solutions

Science - Useful Links

Class 6 Science NCERT Solutions (Curiosity)
Class 7 Science NCERT Solutions (Curiosity)
Class 8 Science NCERT Solutions (Curiosity)
Class 9 Science NCERT Solutions (Exploration)
Class 10 Science NCERT Solutions

Interesting

Learn English
Learn Excel
Learn Tally
Learn GST (Goods and Services Tax)

Class 6

Class 7

Class 8

Class 9

Class 10

Class 11

Class 12

Courses

Interesting

Popular

Class 6

Class 7

Class 8

Class 9

Class 10

Class 11

Class 12

Courses

Interesting

Popular

Example 15 (ii) - Chapter 1 Class 9 Number Systems

Davneet Singh