Answer:
45 square feet
Step-by-step explanation:
Area of square and area of rectangle:
Area of square = 81 square feet
[tex]\sf \boxed{Side \ of \ square = \sqrt{area}}[/tex]
[tex]\sf = \sqrt{81}\\\\ = \sqrt{9*9}\\\\ = 9 \ feet[/tex]
height = 5 ft
length of wall = 9 ft
Area of one wall = length * height
= 9 * 5
= 45 square feet