27 feet
Explanation:
We know that the area of a rectangle is myltiplying the two side lengths (length x width)
If the area is 243 square feet, and one dimension is 9 feet, we will need to DIVIDE the area by one side length to know the other length:
243 ÷ 9 = 27
PLS say if my answer was right, if it was, brainliest please!
-SpaceMarsh
