Using the perimeter concept, it is found that:
D) 6w=42;l=14
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The perimeter of a rectangle of length l and width w is given by:
[tex]P = 2(l + w)[/tex]
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42 feet of fencing means that [tex]P = 42[/tex]
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Length twice the width, thus:
[tex]l = 2w[/tex]
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Solving the equation:
[tex]P = 2(l + w)[/tex]
[tex]42 = 2(2w + w)[/tex]
[tex]6w = 42[/tex]
[tex]w = \frac{42}{7} = 7[/tex]
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The length is:
[tex]l = 2w = 2(7) = 14[/tex]
Thus, the correct option is:
D) 6w=42;l=14
A similar problem is given at https://brainly.com/question/16642085