Uh oh! Wolfram|Alpha doesn't run without JavaScript.
Please enable JavaScript. If you don't know how, you can find instructions
here
.
Once you've done that, refresh this page to start using Wolfram|Alpha.
Write solve -4 <= x and x <= 1 or 9 <= x in set-builder notation
Write solve -4 <= x and x <= 1 or 9 <= x in set-builder notation
Natural Language
Math Input
Extended Keyboard