Find the Zeroes of the Functions Algebraically $f ( x ) = \sqrt { 5 x } - 9$

Multiple Choice

Find the zeroes of the functions algebraically.
$f ( x ) = \sqrt { 5 x } - 9$

A) $x = \pm \frac { 9 } { 5 }$
B) $x = \pm \frac { 81 } { 5 }$
C) $x = \frac { 9 } { 5 }$
D) $x = \frac { 81 } { 5 }$
E) no real zeroes