Question

"Question 1 The cost of a notebook is twice the cost of a pen. Write a linear equation in two variables to represent this statement. (Take the cost of a notebook to be Rs x and that of a pen to be Rs y.)

Class 9 - Math - Linear Equations in Two Variables Page 68"

Answer 1

1 notebook = y
Cost of 1pen = y

x= 2y
=> x-2y+0 = 0

Answer 2

To write a given statement or a word problem in the form of a linear equation in two variables , first identify the variable quantities & assume them as x & y .

Then write the given condition in term of x & y and convert it in the form of ax+by+c =0  which is the required linear equation in two variables.

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Solution:

Let the pen cost y & the notebook cost x.

A.T.Q

Cost of Notebook =2(cost of pen)

 

X=2y

x – 2y +0=0

Which is the required linear equation in two variables.

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Hope this will help you....