Let's look at the equation for a perimeter:
P=Width * Length
We also have another equation for P:
P
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134ft
We know Width(29ft), so let's substitute:
(29)(Length)
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134
If we isolate Length, by dividing 134/29, we get:
Length
which simplifies to about 4.6207
Therefore, I believe all possible values for the Length of the deck would be:
(
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, ∞)
Or: {x(x≥
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)}
Hopefully this helps!