Answer:
21 ft by 27 ft
Explanation:
You want the dimensions of a rug with an area of 567 square feet such that it fits in a 25 ft by 31 ft room with a uniform space all around.
Setup
We note the room is 31-25=6 ft longer than it is wide. Since the rug has a uniform border around it, the rug dimensions will be 6 ft longer than wide. We want the rug area to be 567 square feet, so for width w we have ...
w(w+6) = 567
Solution
w² +6w +9 = 576 . . . . . . add 9 to complete the square
(w +3)² = 24² . . . . . . . . express as squares
w +3 = 24 . . . . . . . . . positive square root
w = 21 . . . . . . . . . . subtract 3 to find the width
w+6 = 27 . . . . . . add 6 to find the length
The rug should have dimensions 21 ft wide by 27 ft long.
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Additional comment
The uniform strip of floor around the rug will be 2 feet wide.