Question

What is the length of the side of a cube if its lateral surface area is $4{\text{cm}}^2$?

• A. 1 cm
• B. 4 cm
• C. 2 cm
• D. 3 cm

Answer 1

The correct option is A 1 cm

$\text{LSA of a cube}=4a^2,\text{where 'a' is the side of the cube.}$

$\text{Given, LSA}=4{\text{cm}}^2\text{Then,}4a^2=4{\text{cm}}^2\Rightarrow a^2=1{\text{cm}}^2\Rightarrow a=\pm \sqrt{1}\text{cm}$
$\therefore a=1\text{cm}$
(Length is always positive. Hence $-\sqrt{1}=-1$ is not considered.)