The answer you are looking for is 14 inches.
When finding the area of a square, you multiply the length and the width together or square (^2) a single side. Since all the sides are the same length, and you have the area, you'd simply find the square root of 196. This would give you 14 as an answer.
To check this, multiply 14 by 14, and you'll get an area of 196.
I hope this helps!