Problem #WSP-000241

Problem

For every pair of integers $a$ , $b$ , we define an operator $a \otimes b$ with the following three properties.
1. $a \otimes a = a + 2$ ;
2. $a \otimes b = b \otimes a$ ;
3. $\frac{a \otimes (a + b)}{a \otimes b} = \frac{a + b}{b} .$
Calculate $8 \otimes 5$ .

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