Question

Write a linear equation in two variables to represent the following statement.

The cost of a pen is thrice the cost of a pencil

• A. $x=3y,$ where $x=$ cost of a pen and $y=$ cost of a pencil.
• B. $x=2y,$ where $x=$ cost of a pen and $y=$ cost of a pencil.
• C. $2x=3y,$ where $x=$ cost of a pen and $y=$ cost of a pencil.
• D. $x=y$, where $x=$ cost of a pen and $y=$ cost of a pencil.

Answer 1

Answer: (A)

$x=3y,$ where $x=$ cost of a pen and $y=$ cost of a pencil.

Let the cost of a pen be $x$ and the cost of a pencil be $y$
According to the statement, cost of a pen is thrice the cost of a pencil

$\Rightarrow x=3y$
$\Rightarrow x-3y=0$ which is a linear equation in two variables