The area of a square is 441 sq cm. what is length os its side?

1 Answer
Mar 10, 2018

21 cm

Explanation:

Sometimes it's helpful to look at a picture of the problem so that you can think about it easier. Here is a diagram of a square with side #a#.

http://mathworld.wolfram.com/Square.html

How do you find the area of a square?
You multiply the length of it's side (#a#) times itself (#a#) OR:
#area = a xx a #
#area = a^2#

Since they already told us that the area is #441 cm^2# we also know that:
#area = 441#

Let's substitute that into the first equation :
#area = a^2#
#441 = a^2#
#sqrt441= a#
#21 cm = a#

CHECK: If each side is 21, then
#441 = 21 xx 21 #
#441 = 441 #
True! So we know that the length of each side is 14.