Answers:
Length = 270 feet
Width = 45 feet
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Work Shown:
x = width
6x = length, since it is 6 times the width
P = perimeter of rectangle
P = 2*(Length + Width)
P = 2*(6x + x)
P = 2*(7x)
P = 14x
Plug in the given perimeter P = 630 and solve for x.
P = 14x
14x = P
14x = 630
x = 630/14
x = 45
The width is 45 feet.
The length must be 6x = 6*45 = 270 feet.