Question

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 $₹x$ and that of a pen to be $₹y$)

Answer 1

Forming a linear equation:

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

Let,

The cost of a notebook $=₹x$

The cost of a pen $=₹y$

As per the given statement

The cost of a notebook $\left(x\right)$ is twice the cost of a pen$\left(y\right)$.

$$\begin{gathered} x=2y \\ \Rightarrow x-2y=0 \end{gathered}$$

Therefore, $x-2y=0$ is the linear equation in two variables that represent the given statement.