Which Equation Does Not Represent $y$ As a Function Of $x$ ?
A)

Multiple Choice

Which equation does not represent $y$ as a function of $x$ ?

A) $x = - 9 y + 2$
B) $x = - 1$
C) $y = 7 x - 9$
D) $y = \left| 6 - x ^ { 2 } \right|$
E) $y = \sqrt { - 9 + 6 x }$