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Define x :
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Let x be the width.
Width = x
Length = 2x + 6
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Formula :
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Perimeter = 2(L + W)
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Find x :
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Given Perimeter = 84
84 = 2 (2x + 6 + x)
84 = 2(3x + 6)
84 = 6x + 12
6x = 84 - 12
6x = 72
x = 72 ÷ 6
x = 12m
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Find Length and Width
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Width = x = 12m
Length = 2x + 6 = 2(12) + 6 = 30m
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Answer: The width is 12m and the length is 30m.
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