SOLUTION: Perimeter of rectangle is 28 feet. The difference between 4 times the length and 3 times the width is 21 feet. What is the dimension. Please clear, precise instructions.

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Question 439497: Perimeter of rectangle is 28 feet. The difference between 4 times the length and 3 times the width is 21 feet. What is the dimension. Please clear, precise instructions.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Perimeter of rectangle is 28 feet. The difference between 4 times the length and 3 times the width is 21 feet. What is the dimension.
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Perimeter = 2(length + width)
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4L-3W = 21
W = (4L-21)/3
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Equation:
28 = 2(L + [(4L-21)/3])
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14 = (L + (4/3)L - 7)
14 = (7/3)L - 7
21 = (7/3)L
L = (3/21)7
Length = 1 ft.
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Solve for "w":
W = (4*1-21)/3
W = -17/3 ft.
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That doesn't make any sense. Width cannot be negative.
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Cheers,
Stan H.