NCERT Class 9 Solutions: Linear Equation in Two Variable (Chapter 4) Exercise 4.2 – Part 1
Linear equation
Q1 Which one of the following option is true, and why?
has

A unique solution

Only two solution

Infinitely many solutions
Solution:

Infinitely many solutions

Because a linear equation in two variables has infinitely many solutions. We keep changing the value of and solve the linear equation for the corresponding value of.
Q2 Write four solutions for each of the following equations:
Solution:
i)
For ,
Therefore, is a solution of this equation.
For ,
Therefore, is a solution of this equation.
For,
Therefore, is a solution of this equation.
For ,
⇒
Therefore, is a solution of this equation.
Four solutions of is ,
ii)
For
Therefore, is a solution of this equation.
For ,
⇒
Therefore, is a solution of this equation.
For ,
Therefore, is a solution of this equation.
For
Therefore, is a solution of this equation.
Four solution of
iii)
For ,
Therefore, is a solution of this equation.
For
Therefore, is a solution of this equation.
For
Therefore, is a solution of this equation.
For
Therefore , is a solution of this equation.
Four solution of is