Domain: (-infinity, +infinity) Range: [0, +infinity)
The answer to a division problem
Fermat's little theorem states that

≡a mod p
If we divide both sides by a, then

≡1 mod p
=>

≡1 mod 17

≡1 mod 17
Rewrite
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mod 17 as

mod 17
and apply Fermat's little theorem

mod 17
=>

mod 17
So we conclude that
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≡1 mod 17
The max occurs when length=width
so
perimiter=16
and L=W
P=2(L+W)
16=2(L+L)
16=2(2L)
16=4L
4=L
the dimentions are length and width are 4 meters
aera will be 16 square meters