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.
graph(2x, 21/x, 2x + 21/x, x=-10..10, y= -20..20)
graph(2x, 21/x, 2x + 21/x, x=-10..10, y= -20..20)
Natural Language
Math Input
Extended Keyboard