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

Last updated at May 29, 2018 by Teachoo

Last updated at May 29, 2018 by Teachoo

Transcript

Ex 3.2,3 On comparing the ratios 1/ 2 , 1/ 2 & 1/ 2 , find out whether the following pair of linear equations are consistent, or inconsistent. 3x+ 2y= 5 ; 2x 3y= 7 3x + 2y 5 = 0 2x 3y 7 = 0 a1 = 3 , b1 = 2 , c1 = 5 & a2 = 2 , b2 = 3 , c2 = 7 Since 1/ 2 1/ 2 We have a unique solution Therefore, our system is consistent. Ex 3.2,3 On comparing the ratios 1/ 2 , 1/ 2 & 1/ 2 , find out whether the following pair of linear equations are consistent, or inconsistent. (ii) 2x -3y = 8 ; 4x - 6y = 9 2x 3y 8 = 0 4x 6y 9 = 0 a1 = 2, b1 = 3 , c1 = 8 a2 = 4, b2 = 6, c2 = 9 Since 1/ 2 = 1/ 2 1/ 2 We have no solution. Therefore, our system is inconsistent. Ex 3.2,3 On comparing the ratios 1/ 2 , 1/ 2 & 1/ 2 , find out whether the following pair of linear equations are consistent, or inconsistent. (iii) 3/2x + 5/3y = 7 ; 9x - 10y = 14 3/2 + 5/3 7 =0 9x 10y 14 = 0 a1 = 3/2 , b1 = 5/3 , c1 = 7 & a2 = 9 , b2 = 10, c2 = 14 Since 1/ 2 = 1/ 2 1/ 2 We have no solution. Therefore, our system is inconsistent. Ex3.2,3 On comparing the ratios 1/ 2 , 1/ 2 & 1/ 2 , find out whether the following pair of linear equations are consistent, or inconsistent. (iv) 5x 3y = 11 , -10x + 6y = -22 5x 3y 11 = 0 10x + 6y + 22 = 0 a1 = 5 , b1 = 3 , c1 = 11 & a2 = 10 , b2 = 6, c2 = 22 Since 1/ 2 = 1/ 2 = 1/ 2 We have infinitely many solutions Therefore, our system is consistent. Now we solve our equations graphically Ex 3.2,3 On comparing the ratios 1/ 2 , 1/ 2 & 1/ 2 , find out whether the following pair of linear equations are consistent, or inconsistent. (v) 4/3 x + 2y = 8 ; 2x + 3y = 12 4/3 x + 2y 8 = 0 2x + 3y 12 = 0 a1 = 4/3 , b1 = 2 , c1 = 8 & a2 = 2, b2 = 3 c2 = 12 Since 1/ 2 = 1/ 2 = 1/ 2 We have infinite solutions. Therefore, our system is consistent.

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Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 8 years. He provides courses for Maths and Science at Teachoo. You can check his NCERT Solutions from Class 6 to 12.