Question 282715
L = length
W = width
P = 2L + 2W = perimeter
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P = 40  :: given
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L = 4W -5  :: length is 5 less than 4*Width
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Substitute and solve for W.
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2L + 2W = P
2(4W-5) + 2W= 40
8W -10 + 2W = 40
10W -10 = 40
10W = 50
W = 5
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L = 4W-5
L = 4(5) -5
L = 20 - 5
L = 15
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Checking the perimeter will tell if this is the right answer
2L + 2W = 40??
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2(15) = 30
2(5) = 10
30+10 = 40
Correct.
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Answer:
The dimensions of the rectangle are length = 15 and width = 5.
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Done.