Find All Solutions of the Equation $$1 - \frac { 4 } { x } - \frac { 21 } { x ^ { 2 } } = 0$$

Multiple Choice

Find all solutions of the equation
$$1 - \frac { 4 } { x } - \frac { 21 } { x ^ { 2 } } = 0$$

A)
$x = - 7$
$x = - 3$


B)
$x = 7$
$x = - 3$

C)
$$\begin{array} { l } x = - 7 \\x = 3\end{array}$$

D)
$x = 7$

$x = 3$

E)
None of the above