McAdoo connected on 10-of-14 shots and Marcus Paige added 15 points for the Tar Heels (10-3), who won a third straight.
Leslie McDonald and Brice Johnson each came off the bench to pop in 14 points as North Carolina notched the 2,100th win in school history.
The Seahawks (6-9) were led by Cedrick Williams with 18 points and nine rebounds.
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