Well, it depends if its positive or negative. 2 positive integers will equal a positive, 2 negatives will equal a negative. A negative and a positive will depend.
Answer:

Step-by-step explanation:
h(x) + g(x) = 

Add them together and subtracct thee total.
Since the two lines are parallel then they have the same slope which = 1/3
since the line passes through (-6 , -8)
y+8 = (1/3)(x+6)
3y + 24 = x + 6
x - 3y = 18 is the equation