From the table:
at x = -1 , f(x) = -4 and g(x) = 4
So, h(x) = f(x) + g(x) = -4 + 4 = 0
at x = 0 , f(x) = -1 and g(x) = 1
So, h(x) = f(x) + g(x) = -1 + 1 = 0
At x = 1 , f(x) = 2 and g(x) = 1
So, h(x) = f(x) + g(x) = 2 + 1 = 3
At x = 2 , f(x) = 5 and g(x) = 4
so, h(x) = f(x) + g(x) = 5 + 4 = 9
At x = 3 , f(x) = 8 and g(x) = 9
So, h(x) = 8 + 9 = 17
See the attached figure which represents the table between x and h(x)