Let f(x)=3x-5. Find
(A) f(3)
Substitute 3 for x and simplify
f(x)=3x-5
f(3)=3(3)-5
f(3)=9-5
f(3)=4
(B) f(h)
Substitute h for x
f(x)=3x-5
f(h)=3h-5
(C) f(3)+f(h)
Add the answers to (A) and (B) and simplify:
f(3)+f(h) = 4+3h-5
f(3)+f(h) = -1+3h
(D) f(3+h)
Substitute 3+h for x and simplify
f(x)=3x-5
f(3+h)=3(3+h)-5
f(3+h)=9+3h-5
f(3+h)=4+3h
Edwin