To create the needed new government the founders compromised on this issue?

Great compromise(Connecticut plan): set up a bicameral(two house) legislature that gave representation both based on population and state equality.

3/5 compromise:allowed slaves to count as 3/5 of people in the census striking a ballance for states that had large slave populations and those who didn't

another agreement that was met was to not talk about slavery until 1820. founders knew this would be a dividing issue and were afraid it would tear the new country apart.