Answer: [tex]D. h^{2}+9h+23[/tex]
Step-by-step explanation:
[tex]f(x)=x^{2} +3x+5[/tex]
1. Input (3+h) instead of x.
[tex]f(3+h)=(3+h)^{2} +3(3+h)+5\\[/tex]
2. Get rid of parentheses.
[tex]f(3+h)=9+6h+h^{2} +9+3h+5\\[/tex]
[tex]f(3+h)=h^{2}+9h+23[/tex]
Therefore, D is the answer.
