<PRE><B>Question 75711</B>
&quot;The difference between the width and the length of a field is 12 m.&quot; 
This means: If width = w; then (w+12) = length
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Find its dimensions if a fence 160 m in length encloses it.
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Perimeter:
 2L + 2W = 160
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Substitute (w+12) for L, solve for w
2(w+12) + 2w = 160
2w + 24 + 2w = 160
4w = 160 - 24
4w = 136
w = 136/4
w = 34 m is the width
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34 + 12 = 46 m is the length:
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Check using the perimeter:
2(46) + 2(34) = 
92 + 68 = 160
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The length of a rectangle is found by doubling thw width and subtracting 3 m.
This means L = 2W - 3
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 Find its dimensions if the perimeter is 84 m.
Substitute (2w-3) for L in the perimeter equation and solve for w
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Do it exactly like the 1st one. 
You can email me if you have difficulty with this
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