What is the | for? Is it a mathematical symbol?
Just being used to "group" the two equations together - more typographic than mathematic. If it was |x| that would mean absolute value.
BTW, visually I get this:
b² (<-y²->) x² (<-y²->) a²
]]>b, y, x, and then y, x, a.
I don't believe any such triplets exist, although I can't prove it.
]]>Other than that, I can only come up with the restrictions:
0 ≤ y² ≤ x² ≤ a²
0 ≤ b² ≤ x² ≤ a²
By using the fact that squares have to be positive, so x² and y² must be positive, and thus b² has to be less than or equal to x², since y² is at least 0, and at most, x².
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