If $y^2=3x-7$ , is y a function of x?

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Answer 1 · 2015-02-10T00:47:48

Yes; although the Domain of $x$ will be limited (assuming by "function" we mean a "real value function")

$y^2 = 3x - 7$ can be re-written as

$y = sqrt(3x - 7)$
which gives a unique value provided $x>= 7/3$

If $x < 7/3$ this equation gives an Imaginary value for y, so it is still a function; it is just not a real valued function).

If y^2=3x-7y^2=3x-7, is y a function of x?