Find (f ° g) (x) and (g ° f) (x)

f (x) = 7x-4, g (x) = 5-3x

(f ◦ g) (x) = f (g (x))

substitute x = g (x) = 5 - 3x into f (x)

f (g (x)) = f (5 - 3x) = 7 (5 - 3x) - 4 = 35 - 21x - 4 = 31 - 21x

(g ◦ f) (x) = g (f (x))

substitute x = f (x) into g (x)

g (f (x)) = 5 - 3 (7x - 4) = 5 - 21x + 12 = 17 - 21x