Check sibling questions

Ex 3.2, 1 Class 10 Maths - Form pair of linear equations and find

Ex 3.2, 1 - Chapter 3 Class 10 Pair of Linear Equations in Two Variables - Part 2
Ex 3.2, 1 - Chapter 3 Class 10 Pair of Linear Equations in Two Variables - Part 3
Ex 3.2, 1 - Chapter 3 Class 10 Pair of Linear Equations in Two Variables - Part 4
Ex 3.2, 1 - Chapter 3 Class 10 Pair of Linear Equations in Two Variables - Part 5
Ex 3.2, 1 - Chapter 3 Class 10 Pair of Linear Equations in Two Variables - Part 6

This video is only available for Teachoo black users

 

Solve all your doubts with Teachoo Black (new monthly pack available now!)


Transcript

Ex 3.2, 1 Form the pair of linear equations in the following problems & find their solutions graphically (i) 10 students of Class X took part in a Mathematics quiz. If the number of girls is 4 more than the number of boys, find the number of boys and girls who took part in the quiz. Let Number of Girls who took part in the quiz be x & Number of Boys who took part in the quiz be y Given Total 10 students took part in the quiz ∴ Number of girls + Number of boys = 10 x + y = 10 Also, Number of girls is 4 more than boys Number of girls = 4 + Number of boys x = 4 + y x – y = 4 Now, plotting equations x + y = 10 ...(1) x − y = 4 …(2) For Equation (1) x + y = 10 Putting x = 4 4 + y = 10 y = 10 − 4 y = 6 So, x = 4, y = 6 is a solution i.e. (4, 6) is a solution Putting y = 4 x + 4 = 10 x = 10 − 4 x = 6 So, x = 6, y = 4 is a solution i.e. (6, 4) is a solution For Equation (2) x − y = 4 Putting y = 0 x − 0 = 4 x = 4 So, x = 4, y = 0 is a solution i.e. (4, 0) is a solution Putting x = 6 6 − y = 4 6 − 4 = y y = 2 So, x = 6, y = 2 is a solution i.e. (6, 2) is a solution We will plot both equations on the graph Therefore, Solution of the equations is (7, 3) Thus, Number of girls in the quiz competition = x = 7 Number of boys in the quiz competition = y = 3

Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.