plot y = 2*(x + 1), y = 2*(x - 1), y = -2*(x + 1), y = -2*(x - 1), x = -1 to 1, y = -2 to 2

Uh oh! Wolfram|Alpha doesn't run without JavaScript.

Please enable JavaScript. If you don't know how, you can find instructionshere.Once you've done that, refresh this page to start using Wolfram|Alpha.