Answer:
see explanation
Step-by-step explanation:
(a)
(f + g)(x) = f(x) + g(x)
f(x) + g(x) = 6x - 2 + 2x + 4 = 8x + 2
(b)
(f - g)(x) = f(x) - g(x)
f(x) - g(x) = 6x - 2 - (2x + 4) = 6x - 2 - 2x - 4 = 4x - 6