Step-by-step explanation:

f (x) = x + 7

g (x) = 2x - 3

(f - g)(x) = f (x) - g (x)

(f - g)(x) = x + 7 - (2x - 3)

(f - g)(x) = x + 7 - 2x + 3

(f - g)(x) = 10 - x

I hope this helps