Question

1.
EXERCISE 4.1
The cost of a notebook is twice the cost of a pen. Write a linear equation in two
variables to represent this statement.​

Answer 1

Answer:

Let the cost of a notebook = Rs x

The cost of a pen = y

According to the condition, we have

[Cost of a notebook] = 2 × [Cost of a pen]

i.e. [x] = 2 × [Y]

or x = 2y

or x – 2y = 0

Thus, the required linear equation is

X – 2y = 0.

Answer 2

Let the cost of a notebook to be = ₹ x

Let the cost of a pen to be = ₹ y

According to the question,

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

i.e., Cost of a notebook = 2×Cost of a pen

$x = 2y$

$x - 2y = 0$

x-2y = 0 is the linear equation in two variables yo represent the statement 'The cost of a notebook is twice the cost of a pen'.