Question

The area of a square is $400c{m}^2.$ The length of its side is$:$

• A. $10cm$
• B. $20cm$
• C. $30cm$
• D. $15cm$

Answer 1

The correct option is B

$20cm$

It is given that area of a square $=400c{m}^2$

Let $a$be the side of the square

Area of square $=a^2$

$a^2$$=400$

$a=\sqrt{400}$

$a=20cm$

Hence, the side of the square is $20cm.$