Question

What will happen to the area of a rectangle, if its length and breadth both are tripled?

Answer 1

Finding the area of a rectangle when length and breadth both are tripled

Let’s say the area of the rectangle is $A$.

The length and breadth of the rectangle be ${}^{\prime }{l}^{\prime }$ and ${}^{\prime }{b}^{\prime }$ respectively.

Therefore, the area of the rectangle

$A=$ Length $\times$ Breadth

$A=lb\left(i\right)$

Now,

After tripling the length and the breadth of the rectangle,

New length $=3l$

New breadth $=3b$

According to question,

New Area

$=$ New length $\times$ New breadth

$=3l\times 3b$

$=(3\times 3)lb$

$=9lb$

$=9A\text{[from equation}\left(i\right)]$

$=$ nine times the original area

Therefore,

The new area will be $9$ times of the original area.