How do you evaluate (f+g)(-2) where f(x) = x^2+9x+18 and g(x) = -4x-3?

1 Answer
Nov 13, 2017

-1

Explanation:

f(x)=x^2+9x+18 and g(x)=-4x-3

defines (f+g)(x)=f(x)+g(x)

then

(f+g)(x)=x^2+9x+18-4x-3

(f+g)(x)=x^2+5x+15

for x=-2

(f+g)(-2)=(-2)^2+9(-2)+15

(f+g)(-2)=-1