Class 9 CH 3 ex.no.3.1 Q.no.1

Question - 1. The cost of a notebook is twice the cost of a pen. Write a linear equation in two variables to represent the above statement.

Solution:- Let the cost of a notebook be x and that of a pen be y.

According to question,

The cost of a notebook is twice the cost of a pen

Or, x = 2y

Or, x - 2y = 0.