Which number replaces the question mark ?

Question

Answer 1

4 is the missing digit. 37= (2+1 2+5)
3 7

So 92= (3+5 8+4)
8 12
8+1 2
9 2

Answer 2

This question is ambiguous. Besides 4, -5 is also possible by following logic, :

3+7 = 5+1+2+2
9+2 = 8+3+5+(-5)

Atleast one more graph should have been provided or it should be mentioned that answer is confined to natural numbers.