I think first of all you should convert both masses to weight by
W= mg ( gravity is 9.8m/s^2)
W= (6)(9.8)= 58.8N
W= (5)(9.8)= 49N
Resultant force = 58.8-49= 9.8N
Final answer:
9.8N
I’m really sorry if the answer turned out to be wrong but I tried my best so good luck!!