Question 1001185
<pre>
{{{x^2+16}}} cannot be factored as {{{(x+4)(x-4)}}}.
You are confusing {{{x^2+16}}} with {{{x^2-16}}} which can
be factored that way.

But Since 2 is positive and {{{x^2+16}}} is always positive,
we can divide both sides by 2 and multiply both sides by
{{{x^2+16}}} and get {{{x<=0}}} which in interval notation
is  {{{matrix(1,5,    "(",-infinity,",",0,"]")}}}

Edwin</pre>