Yes it is possible to have apps from more than one ID.
Go to the purchased section of App Store. Change the ID to the second ID and login to that account. You can then see the Apps that have been purchased by that account. Download the apps you want to add to the iPad.
When you go to backup the other set of apps on your computer you will need to "authorize" the computer for account. When there are updates you will need to okay the update with the appropriate password for the account used to purchase the app originally.
Joel
Sent from my iPad
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