I learned how to do this from [here][1]

I did this from a Linux PC with ADB installed.  It may be possible from a Windows PC with ADB installed but I could never get the tablet to connect as an installer over USB on Windows.

> Turns out it was dead simple, really, it came rooted. Here’s how I
> installed Superuser on it so I can use apps that use root.

> 1. Download [superuser.zip][2]
  
> 2. Unzip `superuser.zip`
  
> 3. `adb root` (to run adb as root user on the tablet)    

> 4. `adb remount` 
 
> 5. `adb push Superuser.apk /system/app/`       

> 6. `adb push armeabi/su /system/xbin/su`        

> 7. `adb shell chmod 6755 /system/xbin/su`        

> 8. `adb shell ln -s /system/xbin/su /system/bin/su`       

> 9. `wget https://github.com/koush/Superuser/raw/master/init.superuser.rc`        

> 10. `adb push init.superuser.rc /`

  [1]: https://annoyingtechnicaldetails.wordpress.com/2014/07/31/rooting-a-20-tablet-azpen-a727/
  [2]: http://download.clockworkmod.com/superuser/superuser.zip