Answer
$(a)\; x=3$.
Work Step by Step
The given expression is
$=\frac{x}{x^2-9} $
(a) Substitute $x=3$.
$=\frac{3}{3^2-9} $
Simplify.
$=\frac{3}{9-9} $
$=\frac{3}{0} $
Not defined.
(b) Substitute $x=1$.
$=\frac{1}{1^2-9} $
Simplify.
$=\frac{1}{1-9} $
$=\frac{1}{-8} $
$=-\frac{1}{8} $
(c) Substitute $x=0$.
$=\frac{0}{0^2-9} $
Simplify.
$=\frac{0}{0-9} $
$=\frac{0}{-9} $
$=0 $
(d) Substitute $x=-1$.
$=\frac{-1}{(-1)^2-9} $
Simplify.
$=\frac{-1}{1-9} $
$=\frac{-1}{-8} $
$=\frac{1}{8} $
Hence, the correct answer is $(a)\; x=3$.
