Enter a simplified expression to represent the situation. A square swimming pool is surrounded by a cement walkway with a uniform width. The swimming pool has a side length of (x − 6) feet. The side length of the entire square area including the pool and the walkway is (x + 4) feet.

Enter an expression for the area of the walkway. Then find the area of the cement walkway when x = 9 feet.

The area of the walkway is ft2.

When x = 9 feet, the area of the cement walkway is
ft2.