This is your first encounter with an armored vehicle. The T-72 tank is heavily armored, and direct gunfire will do little. Your primary objective is to destroy it or disable it for Fulton recovery. For destruction, you'll need explosives like Grenades, RPGs, or the M1 Bazooka (if developed). Aim for the rear of the tank, as it's its weakest point.
To capture the tank, you need to defeat all the accompanying infantry first. Once the infantry is dealt with, the tank commander will often pop out of the hatch. Shoot him with a tranquilizer gun to put him to sleep, then use the Fulton Recovery System on the tank itself. This is a great way to acquire powerful vehicles for your Outer Ops. Stay mobile, use cover, and prioritize the infantry first.