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) $x = 2 y + 5$
B) $\quad x = 6$
C) $y = - 5 x - 7$
D) $y = \left| 6 + 9 x ^ { 2 } \right|$
E) $y = \sqrt { - 8 + 4 x }$