Respuesta :

f(x)=3x+8 and g(x)=6x+6

(f - g)(x) = f(x) - g(x)
 
              = 
3x+8 - (6x + 6) = 3x - 6x + 8 - 6 = -3x + 2

(f - g)(x) =  -3x + 2

(f - g)(-1) =  -3*-1 + 2 = 3 + 2 = 5

(f - g)(-1) = 5