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Answers: </h3>
Width = 10 feet
Length = 40 feet
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Explanation:
W = width
L = 4W = four times the width = length
P = perimeter
P = 2*(W+L)
P = 2*(W+4W)
P = 2(5W)
P = 10W
The perimeter is 100 feet.
P = 100
10W = 100 .... plug in P = 10W
W = 100/10 .... divide both sides by 10
W = 10
The width is 10 feet.
L = 4W
L = 4*10
L = 40
The length is 40 feet.
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Check:
P = 2(L+W)
P = 2(40+10)
P = 2(50)
P = 100
or another way to check is to add up the four sides {10, 40, 10, 40}
10+40+10+40 = 50+50 = 100
This confirms the answer.