The Trotters made a flying start and were 3-0 up inside 10 minutes courtesy of goals from Darren Pratley, Mark Davies and Craig Dawson, before Dawson added a second in the second half.
Wanderers are now 14th, 10 points off the top six with back-to-back games against Peterborough and Barnsley to come.
"It shows you what we are capable of and a result like this has been coming," added Freedman.
"It's been difficult for the players and the club since they suffered relegation.
"There has been a lot of expectation but I know how good they can be. It's just very pleasing to beat a good Hull team."
Asked whether Wanderers can still mount a promotion challenge he added: "Nothing is impossible. The players are committed to winning every single game."
To cap a good afternoon, Freedman introduced January signing, Mohamed 'Medo' Kamara for a debut off the bench and gave a late run out to David Wheater - his first appearance since damaging cruciate ligaments last May.