#### Answer

The length of each side of the square room is 15 feet.
The dimensions are 15 feet $\times$ 15 feet.

#### Work Step by Step

Area of a square is Length of side (s) $\times$ Length of side i.e., $A= s\times s=s^2$
It is given that Area (A) of the square room is 225 square feet.
$225 = s^2$
Using the square root property,
$±\sqrt225=s$
$± 15=s$
Since the length of the side cannot be negative, the length of side = 15 feet.
Therefore, the dimensions of the square room is 15 feet $\times$ 15 feet