Answer: Length = 70 feet
Concept:
Here, we need to know how to find the perimeter of a rectangle.
Perimeter (rectangle) = 2 (l + w)
l = length
w = width
Solve:
Given information
l = l
w = 51 feet
P = 242 feet
Given expression
P = 2 (l + w)
Substitute values into the expression
242 = 2 (l + 51)
Divide 2 on both sides
242 / 2 = 2 (l + 51) / 2
121 = l + 51
Subtract 51 on both sides
121 - 51 = l + 51 - 51
Hope this helps!! :)
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