Answer:
15
Step-by-step explanation:
(3x-1+2x+1)(3) -> 3 is the plug-in for x
3x-1+2x+1=5x
5*3=15
f(x) = 3x -1
g(x) = 2x+1
(f+g)(3)
find g(3) = 2(3)+1 = 6+1 = 7
Then find f(3) = 3(3) -1 = 8
f(3) + g(3) = 7+8 = 15
