Answer
$(-\infty,-\sqrt 5]$ U $[\sqrt 5, \infty)$
Work Step by Step
Simplify the expression on one side
$x^2-5\geq0$
Identify the key numbers by equating to zero
$(-\infty,-\sqrt 5]$
$(\infty,\sqrt 5]$
$[\sqrt 5,\sqrt 5]$
Assign a test value for each interval to determine the sign
$(-\infty,-\sqrt 5]$ U $[\sqrt 5, \infty)$
