Answer:
40 ft
Step-by-step explanation:
Let x represent the average of the length and width. Then the length is (x+2) and the width is (x-2). The area is the product of these:
96 = (x +2)(x -2) = x² -4
100 = x² . . . . . . add 4
10 = x . . . . . . . . square root
Since x is the average of two numbers, their sum is 2x. The perimeter of the yard is twice the sum of length and width, so is 4x = 4·10 = 40.
The perimeter of the yard is 40 feet.
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In case you care, the size of the yard is 8 ft by 12 ft.
