Answer:
The diagonal is 8.9 feet
Explanation:
The formula for a diagonal of a rectangle is √w^2+h^2, with w and h being the width and height. Plug in your numbers to get √7^2+5.5^2. Simplify that into √49+30.25, then to √79.25. Use your calculator to get 8.9022.
The diagonal is 8.9 feet.