Math question?

x^2-4 = (x-2)(x+2)

so h(x) is a factor

h (x)= x + 2 and f (x) = x² - 4 = (x - 2 ) ( x + 2 )
h (x) is a factor of f(x)

f(x) = x² - 4 = (x+2) (x-2), so h(x) is a factor of f(x).