Bubble in my tire for 2009 M35x

[Mohammed]

I went over a large pothole last night and it created a bubble on the side of my front left side tire. I just bought the car 3 weeks ago and the tires are fairly new. I know I cannot replace one tire but can I change only 2 tires in an All Wheel drive?

 

[Sal Collaziano]

I'm not sure why that would be a problem.. Unless I'm missing something...

 

[FourReelSVT]

You can replace just one tire if you have to. How worn down are you others?