# Ex 3.2, 3 - Chapter 3 Class 10 Pair of Linear Equations in Two Variables (Important Question)

Last updated at Dec. 28, 2018 by Teachoo

Last updated at Dec. 28, 2018 by Teachoo

Transcript

Ex 3.2,3 On comparing the ratios ๐1/๐2 , ๐1/๐2 & ๐1/๐2 , find out whether the following pair of linear equations are consistent, or inconsistent. 3x+ 2y= 5 ; 2xโ 3y= 7 3x + 2y โ 5 = 0 2x โ 3y โ 7 = 0 3x + 2y โ 5 = 0 Comparing with a1x + b1y + c1 = 0 โด a1 = 3 , b1 = 2 , c1 = โ5 2x โ 3y โ 7 = 0 Comparing with a2x + b2y + c2 = 0 โด a2 = 2 , b2 = โ3 , c2 = โ7 a1 = 3 , b1 = 2 , c1 = โ5 & a2 = 2 , b2 = โ3 , c2 = โ7 Since ๐1/๐2 โ ๐1/๐2 We have a unique solution Therefore, our system is consistent. Ex 3.2,3 On comparing the ratios ๐1/๐2 , ๐1/๐2 & ๐1/๐2 , find out whether the following pair of linear equations are consistent, or inconsistent. (ii) 2x -3y = 8 ; 4x - 6y = 9 2x โ 3y โ 8 = 0 4x โ 6y โ 9 = 0 2x โ 3y โ 8 = 0 Comparing with a1x + b1y + c1 = 0 โด a1 = 2 , b1 = โ 3 , c1 = โ 8 4x โ 6y โ 9 = 0 Comparing with a2x + b2y + c2 = 0 โด a2 = 4 , b2 = โ 6 , c2 = โ 9 โด a1 = 2, b1 = โ 3 , c1 = โ 8 a2 = 4, b2 = โ6, c2 = โ 9 Since ๐1/๐2 = ๐1/๐2 โ ๐1/๐2 We have no solution. Therefore, our system is inconsistent. Ex 3.2,3 On comparing the ratios ๐1/๐2 , ๐1/๐2 & ๐1/๐2 , find out whether the following pair of linear equations are consistent, or inconsistent. (iii) 3/2x + 5/3y = 7 ; 9x - 10y = 14 3/2 ๐ฅ + 5/3 ๐ฆ โ 7 =0 9x โ 10y โ 14 = 0 ๐/๐ ๐ + ๐/๐ ๐ โ ๐ =๐ Comparing with a1x + b1y + c1 = 0 โด a1 = 3/2 , b1 = 5/3 , c1 = โ 7 9x โ 10y โ 14 = 0 Comparing with a2x + b2y + c2 = 0 โด a2 = 9 , b2 = โ 10, c2 = โ 14 โด a1 = 3/2 , b1 = 5/3 , c1 = โ 7 & a2 = 9 , b2 = โ 10, c2 = โ 14 ๐๐/๐๐ ๐1/๐2 = (3/2)/9 ๐1/๐2 = 3/(2 ร 9) ๐1/๐2 = 1/(2 ร3) ๐1/๐2 = 1/6 ๐๐/๐๐ ๐1/๐2 = (5/3)/10 ๐1/๐2 = 5/(3 ร10) ๐1/๐2 = 1/(3 ร 2) ๐1/๐2 = 1/6 ๐๐/๐๐ ๐1/๐2 = (โ7)/(โ14) ๐1/๐2 = 1/2 Since ๐1/๐2 = ๐1/๐2 โ ๐1/๐2 We have no solution. Therefore, our system is inconsistent. Note: This answer does not match the book answer. If we are wrong, please comment below

Chapter 3 Class 10 Pair of Linear Equations in Two Variables

Example 6
Important

Example 10 Important

Example 11 Important

Example 13 Important

Example 14 Important

Example 19 Important

Ex 3.2, 1 Important

Ex 3.2, 3 Important You are here

Ex 3.2, 6 Important

Ex 3.5, 2 Important

Ex 3.2, 7 Important

Ex 3.6, 1 (i) and (ii) Important

Ex 3.6, 1 (iii) and (iv) Important

Ex 3.6, 1 (v) and (vi) Important

Ex 3.6, 1 (vii) and (viii) Important

Ex 3.6, 2 Important

Class 10

Important Questions for Exam - Class 10

- Chapter 1 Class 10 Real Numbers
- Chapter 2 Class 10 Polynomials
- Chapter 3 Class 10 Pair of Linear Equations in Two Variables
- Chapter 4 Class 10 Quadratic Equations
- Chapter 5 Class 10 Arithmetic Progressions
- Chapter 6 Class 10 Triangles
- Chapter 7 Class 10 Coordinate Geometry
- Chapter 8 Class 10 Introduction to Trignometry
- Chapter 9 Class 10 Some Applications of Trignometry
- Chapter 10 Class 10 Circles
- Chapter 11 Class 10 Constructions
- Chapter 12 Class 10 Areas related to Circles
- Chapter 13 Class 10 Surface Areas and Volumes
- Chapter 14 Class 10 Statistics
- Chapter 15 Class 10 Probability

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Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.