Answer:
24 feet
Explanation:
Let w represent the width of the rectangle. Then its length is 2w, and its area is ...
A = Lw
32 = (2w)(w) = 2w^2 . . . fill in the given values
16 = w^2 . . . . . . . . . . . . divide by 2
4 = w . . . . . . . . . . . . . . take the square root
8 = 2w = L . . . . . . . . . find the length
The dimensions of the yard are 8 feet long and 4 feet wide.
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The perimeter is ...
P = 2(L +w) = 2(8 +4) = 2(12) = 24 . . . . feet
The perimeter of the rectangular back yard is 24 feet.