Explanation:
Shawn's living room is a square, so all four sides are the same length. Area of a square is A = s², and we know the area is 196 ft². If substitute this for A:
196 ft² = s²
Take square root of both sides:
s = √(196 ft²)
s = ±14 ft
Since measurements of lengths can't be negative, s must be +14 ft. So Shawn's living room is 14 ft x 14 ft.