Inputs for flipflops sequential circruits
Try using Q(t) and Q(t+1) while writing your state equations to avoid confusion.
Also just use QA and QB(and their complements if necessary) instead of using "A" and "B" as outputs.

Hope this helps you:

JA(t) = KA(t) = QB(t)

QA(t+1) = (QA(t)' AND JA(t)) + (QA(t) AND KA(t)')

DB(t) = QB(t)'

QB(t+1) = DB(t)

TC(t) = 0

QC(t+1) = QC(t)