Final answer:
Each side of a square deck with an area of 300 square feet is approximately 17.32 feet long, calculated by taking the square root of the area.
Step-by-step explanation:
The student is asking about the length of the sides of a square deck when given the total area that can be covered by a gallon of stain. Since the area of a square is calculated by squaring the length of one side, we can find the length of the sides by taking the square root of the area. In this case, the area is 300 square feet. Therefore, the approximate length of each side of the square deck is the square root of 300.
To calculate it, √300 ≈ 17.32, so each side of the deck is approximately 17.32 feet long. Please remember that this is an approximation and actual coverage could be slightly more or less depending on factors such as the method of application and the surface texture.