remember, |n|≥0 for all real numbers n
so
-|x|=0
times -1
|x|=0
true, x=0, has a solution
|x|=-15
false, can't have negative absolute value
-|x|=12
|x|=-12
false, no negative absolute value
-|-x|=9
|-x|=-9
false, no negative absolute value
-|-x|=-2
|-x|=2
x=2 or -2
true, has solutions
the ones that have no solutions are
|x|=-15
-|x|=12
-|-x|=9
