Answer:
A. lw = (x+6)(x -6); 133 square feet
Step-by-step explanation:
If x is the original length (in feet), when the length is increased by 6 feet, it can be represented by (x+6).
If x is the original width, when it is decreased by 6 feet, it can be represented by (x-6).
The area is the product of length and width, so the new area is ...
lw = (x+6)(x-6)
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Since the original side is 13 ft, the new length is 13+6 = 19 ft, and the new width is 13-6=7 ft. The area is ...
(19 ft)(7 ft) = 133 ft²
