How can I activate used Ipad I purchased and use my appleid
I purchased an Ipad 2, Model A1395, as part of a Kiosk kit. The vendor which sold the kiosk is no longer in business but their appleid is still tied to the Ipad and I cannot activate the Ipad and repurpose it without their credentials. I have my receipt as proof of purchase how can I get the vendor's appleid off of this Ipad and use my appleid going forward?
iPad (4th gen) Wi-Fi, Mac OS X (10.0.x)