Question 430704: The length of a rectanle is fixed at 25 cm. What widths will make the perimeter greater than 92 cm? The width must be greater than ? Cm.
Answer by oberobic(2304)   (Show Source):
You can put this solution on YOUR website! Start with what you know.
First, a rectangle has a perimeter = 2L + 2W.
Second, L=25 is a constant.
Third, you want the perimeter, P = 92 or P > 92.
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P = 2L + 2W
Substitute what you know
92 = 2(25) + 2W
92 = 50 + 2W
Divide through by 2
46 = 25 + W
Subract 25 from both sides
21 = W
or
W = 21
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Always check your answer.
2L + 2W = ??
2(25) + 2(21) = 50 + 42 = 92
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That checks. The value of W = 21 will make the perimeter exactly 92.
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Now make sure you answer the question. It wants the value of W to ensure the perimeter is > 92.
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Answer: W must be greater than 21.
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Done.
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